Python 1 Answers - Code Avengers

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Python 1 Answers

1. Introduction to Python

1.1. The print statement

print("Hello,Monty!")

1.2. Printing numbers

print(3)

print(5+3)

print(20/5)

print(9*9)

1.3. The input statement

name=input("Whatisyourname?")

print(name)

1.4. Joining data in print statements

name=input("Whatisyourname?")

print("Hello"+name)

print(name+"isanicename!")

1.5. Review quiz!

Review Quiz Questions:

1. input()

2. *

3. print(3 + 8 - 4)

4. print("That snake is named " + name)

2. Strings and print statements

2.1. The length of a piece of string

print("Hannah")

print("MontyPython"+"andtheHolyGrail")

print("Spam!"*8)

2.2. Choose the right quotes!

print("Look,thatrabbit'sgotaviciousstreakamilewide!

It'sakiller!")

print('Wearenolongertheknightswhosay"ni",wearenow

theknightswhosay"ekki‐ekki‐ekki‐pitang‐zoom‐boing!"')

print("Thereare10typesofpeopleinthisworld,thosewho

know\"binary\"andthosewhodon't.")

2.3. Printing on more than one line

print("""Hittingenterhere

doeswork!""")

print("Hereisamulti‐line\n"

"printstatement")

2.4. String variables

poem="""Whenyou'rechewingonlife'sgristle

Don'tgrumble,giveawhistle

Andthis'llhelpthingsturnoutforthebest...

And...alwayslookonthebrightsideoflife...

Alwayslookonthelightsideoflife..."""

print(poem)



phrase="Todayyouarefeeling:\n"



mood="Happy"

print(mood)

mood=input("Howareyoufeelingtoday?")

print(mood)



print(phrase+mood)

2.5. Review quiz!

Review Quiz Questions:

1. "

2. \n

3. "

4. '

3. Math calculations and operators

3.1. Math operators

print(2*5+3)

print(5**4)

print(3*8/2)

3.2. BEDMAS - Order of operations

print((7+3)/2)

print(20‐2**2)

print((5+2)*10)

3.3. Identify different types of numbers

result_1=8/2

result_2=3+8

result_3=0.1+0.2

result_4=0.1+0.7



print(result_1)

print(result_2)

print(result_3)

print(result_4)



result_5=0.4*3

print(result_5)

3.4. Calculations with variables

#Createvariables

hourly_rate=15.50

hours_worked=40



#Calculatewagesbasedonhourly_rateandhours_worked

#Rememberyoucanusevariablenamesthesamewayyouwould

usenumbersincalculations

wages=hourly_rate*hours_worked



#Printtheresult

print(wages)

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3.5. Python math review quiz

Review Quiz Questions:

1. **

2. print(2 ** 3 - 1)

3. price

4. print(32 * 4 - (5 + 3))

4. Combining things in print statements

4.1. Joining things in a print statement

hourly_rate=15.50

hours_worked=40

wages=hourly_rate*hours_worked

print("Thisweekyouearned:$"+wages)

4.2. Joining strings with numbers

hourly_rate=15.50

hours_worked=40



wages=hourly_rate*hours_worked



print("Thisweekyouearned:$",wages)

4.3. Joining strings with calculations

#Printsomemathsstatements

print("9x12=",9*12)

print("3‐4=",3‐4)

print("32/8=",32/8)

#Calculatingthecircumferenceofacircle

PI=3.14159

diameter=30

#Hint:Thecircumferenceofacircleispitimesthediameter

print("Thecircumferenceofthecircleis:",PI*diameter)

4.4. Format print statements using the built-in .format() function

#Calculatewages

hourly_rate=15

hours_worked=35



wages=hourly_rate*hours_worked



#Printoutwages

print("Thisweekyouhaveearned:${}".format(wages))



#Printsomemathsstatements

print("3x7={}".format(3*7))

print("32‐16={}".format(32‐16))

print("256+128={}".format(256+128))

4.5. Print more interesting statements with .format()

name=input("Whatisyourname?")

age=input("Howoldareyou?")

print("Really{}?Itmustbenicebeing{}years

old.".format(name,age))

5. Comments and variable names

5.1. Write comments for the humans that read your code!

#Asktheuserforpersonaldetails

name=input("Whatisyourname?")

age=input("Howoldareyou?")

location=input("Whereareyoufrom?")



#Printsummaryofinputforchecking

print("Thisisthedatayouhaveentered:")

print("Name:"+name)

print("Age:"+age)

print("Location:"+location)

5.2. Choose good variable names!

#Askuserforaddressdetails

house_number=input("Whatnumberisyourhouse?")

street_name=input("Whatstreetdoyouliveon?")



address=house_number+""+street_name



#Confirmdatawithuser

print("Youraddressis:{}".format(address))

confirm=input("Arethesedetailscorrect?Y/N:")

5.3. Choose even better variable names

#Gatherfavoritesdata

fave_color=input("Whatisyourfavoritecolor?")

fave_food=input("Whatisyourfavoritefood?")

fave_music=input("Whoisyourfavoriteband/musician?")



#Combinefavoritesintoatastysnacke.g.PurpleMetallica

Pizza

print("SoIguessyouwouldlovetohave{}{}{}atyour

nextparty!".format(fave_color,fave_music,fave_food))

5.4. Write all that punctuation so it's easy to read

perimeter_of_rectangle=2*32+2*16

print("Myhovercraftisfullofeels")

5.5. Python conventions quiz!

Review Quiz Questions:

1. #

2. number_of_students

3. print("Well, that's cast rather a gloom over the evening, hasn't it?")

4. answer_1

6. Turtle drawing basics

6.1. Meet Tia the Turtle

importturtle

tia=turtle.Turtle()

tia.forward(50)

6.2. Move and turn Tia

importturtle

tia=turtle.Turtle()



tia.forward(200)

tia.left(90)

tia.forward(200)

tia.left(90)

tia.forward(200)

tia.left(90)

tia.forward(200)

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6.3. Change the color and size

importturtle

tia=turtle.Turtle()

tia.pensize(10)

tia.color("red")

tia.forward(200)

tia.left(90)

tia.color("green")

tia.forward(200)

tia.left(90)

tia.color("yellow")

tia.forward(200)

tia.left(90)

tia.color("blue")

tia.forward(200)

6.4. Draw some different shapes

importturtle

timmy=turtle.Turtle()

timmy.pensize(5)

#Movetofirstposition

timmy.penup()

timmy.goto(10,60)

timmy.pendown()

#Drawapurplerectangle,120by50

timmy.color("purple")

timmy.forward(120)

timmy.left(90)

timmy.forward(50)

timmy.left(90)

timmy.forward(120)

timmy.left(90)

timmy.forward(50)

#Movetonextposition

timmy.penup()

timmy.goto(420,60)

timmy.setheading(0)

timmy.pendown()

#Drawanorangetrianglewithsidesthatare60pxlong

timmy.color("orange")

timmy.forward(60)

timmy.left(120)

timmy.forward(60)

timmy.left(120)

timmy.forward(60)

6.5. Filling shapes with colors

#Createturtle

importturtle

tina=turtle.Turtle()

tina.color("lightGreen")

tina.pensize(8)

#Drawalightgreensquarewithyellowfill

tina.fillcolor("yellow")

tina.begin_fill()

tina.forward(200)

tina.left(90)

tina.forward(200)

tina.left(90)

tina.forward(200)

tina.left(90)

tina.forward(200)

tina.left(90)

tina.end_fill()

7. Introduction to variables

7.1. Calculate donut orders... Mmmm... Donuts....

#Glazeddonutscost$3,filleddonutscost$4andminidonuts

cost$2



#Calculatetotalcostfororder#1:5glazed,3filledand6

minidonuts

order1_cost=5*3+3*4+6*2



#Calculatetotalcostfororder#2:2glazed,1filledand10

minidonuts

order2_cost=2*3+4+10*2



#Displayordersummaries

print("Order#1comesto:${}".format(order1_cost))

print("Order#2comesto:${}".format(order2_cost))

7.2. Use variables to make code more flexible

#Glazeddonutscost$3,filleddonutscost$4andminidonuts

cost$2

glazed_donut=3

filled_donut=4

mini_donut=2



#Calculatetotalcostfororder#1:5glazed,3filledand6

minidonuts

order1_cost=5*glazed_donut+3*filled_donut+6*

mini_donut



#Calculatetotalcostfororder#2:2glazed,1filledand10

minidonuts

order2_cost=2*glazed_donut+1*filled_donut+10*

mini_donut



#Displayordersummaries

print("""Order#1comesto:${}

Order#2comesto:${}""".format(order1_cost,order2_cost))

7.3. Write a program for game purchases using variables

#Setuppricevariables

ps3_game=20

ps4_game=45



discount=10



#Order#1:1PS3gameand2PS4games

order1_price=1*ps3_game+2*ps4_game



#Order#2:4PS3games,3PS4games

order2_price=4*ps3_game+3*ps4_game‐discount



#Printouttotalordercosts

print("Order1costs:${}".format(order1_price))

print("Order2costs:${}".format(order2_price))

7.4. Ask for user input to make the program interactive

#Setuppricevariables

ps3_game=20

ps4_game=45



#Askfornumberofeachgametobepurchased

num_ps3_games=int(input("HowmanyPS3games?:"))

num_ps4_games=int(input("HowmanyPS4games?:"))



#Calculatetotalforeachtypeofgame

ps3_total=num_ps3_games*ps3_game

ps4_total=num_ps4_games*ps4_game



#Calculatetotalcost

total_cost=ps3_total+ps4_total



#Printouttotalordercost

print("Yourordercosts:${}".format(total_cost))



#Optionalordersummary

print("""Ordersummary‐youordered:

{0}PS3gamesfor${1}

{2}PS4gamesfor${3}""".format(num_ps3_games,ps3_total,

num_ps4_games,ps4_total))

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7.5.

Review Quiz Questions:

1. number = int(input("Please enter a number: "))

2. All of these

3. total_price = 2 * book_price + book_price / 2

4. num_pizzas, total_cost, pizza_price

8. Numbers and variables

8.1. Increment (increase) an integer variable using +=

num_pies=0

print("Lisahas{}pies".format(num_pies))

num_pies+=5

print("Lisahas{}pies".format(num_pies))

8.2. Increment a variable, using another variable

#Askuserforageandyearstoadd

age=int(input("Howoldareyou?"))

years_to_add=int(input("Howmanyyearsdoyouwanttoadd?

"))

#Addyearstoage

age+=years_to_add

#Printresult

print("In{}yearsyouwillbe{}".format(years_to_add,age))

8.3. Use other operators to change a variable

#Setupvariables

number1=35

number2=7

number3=16

#Changevariables

number1‐=10

print(number1)

number2*=4

print(number2)

number3/=8

print(number3)

8.4. Calculate discounts using shorthand operators

#Setuppricevariables

ps3_game=20

ps4_game=45

#TemporarydiscountonPS3games

ps3_game‐=2

#Askfornumberofeachgametobepurchased

num_ps3_games=int(input("HowmanyPS3games?:"))

num_ps4_games=int(input("HowmanyPS4games?:"))

#Calculatetotalforeachtypeofgame

ps3_total=num_ps3_games*ps3_game

ps4_total=num_ps4_games*ps4_game

#Calculatetotalcost

total_cost=ps3_total+ps4_total

#Apply15%discount

total_cost*=0.85

#Printouttotalordercost

print("Youordercosts:${}".format(total_cost))

8.5.

Review Quiz Questions:

1. +=

2. 0.85

3. var_2 -= 3

4. 4

9. Debugging print statements

9.1. Hunting for bugs

print("Acomputerprogrammercanearn6figures!")



print("Shelookedupandyelled\"Watchout!You'llbreak

it!\"")



number=input("What'syourfavoritenumber?")



print("Yourfavoritenumberis:{}".format(number))

9.2. Debug problems with brackets

print(3+2*(5**2))



shoe_size=int(input("Whatsizeareyourshoes?"))



print("Myshoesaretwiceasbig,theyaresize

{}".format(shoe_size*2))

9.3. Debug variables

catch_phrase1="Ni!"

catch_phrase2="Ekki‐ekki‐ekki‐pitang‐zoom‐boing!"



print("Wearetheknightswhosay{}".format(catch_phrase1))

print("Erm,waitaminute...")

print("Wearenolongertheknightswhosay{},wearethe

knightswhosay{}".format(catch_phrase1,catch_phrase2))

9.4. Debug code that uses numbers

donut_price=5



#Askhowmanydonuts

num_donuts=int(input("Howmanygourmetdonutswouldyou

like?"))



#CalculatepriceandapplySuperSaturdaydiscount

print("Butwait!It'sSaturdaysoyouget$1offyourtotal

orderforeachdonutpurchased!")

order_total=num_donuts*donut_price‐num_donuts



#Displayordertotal

print("Thatwillcost:${}".format(order_total))

9.5. Put it all together for some real-world debugging

#Askandgreetbyname

name=input("Whatisyourname?")

print("Hello{}!Let'sworkoutwhatyouearnedthis

week".format(name))



#Askuserforworkdata

hourly_rate=int(input("Howmuchdoyouearnperhour?"))

hours_worked=int(input("Howmanyhoursdoyouworkperday?

"))

days=int(input("Howmanydaysperweekdoyouwork?"))



#Calculatewagesfortheweek

wages=hourly_rate*hours_worked*days



print("Yourpaythisweekbeforetaxis:${}".format(wages))



#Takeoff20%tax

wages*=0.8



print("Aftertax@20%thatis:${}".format(wages))

10. Review lessons 1-9

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10.1. Review print and input statements

name=input("Whatisyourname?")

print(name)

birth_year=int(input("Whatyearwereyouborn?"))

age=2017‐birth_year

print("Youwillbe{}yearsoldthisyear!".format(age))

10.2. Review all that maths!

#Add4to8andthendivideby2

print((4+8)/2)

#Increasescore

score=5

score+=10

print(score)

#Calculateareaofarectangle

length=120

width=75

print("Theareaoftherectangleis{}".format(length*

width))

#Asktheuserfor2numbersandstorethemasvariables.

Don'tforgetint()!

num1=int(input("Chooseanumber:"))

num2=int(input("Chooseasecondnumber:"))

#Printoutthesumofthe2numbers(justbyitself,without

asentence)

print(num1+num2)

10.3. Review working with strings

string1="Thequickbrownfox"

string2="jumpsoverthelazydog"

#Combinethestrings

print(string1+string2)

#PrintCodingisfun!8times

print("Codingisfun!"*8)

#Addthecalculation

print("27/3=",27/3)

#Includethephonenumber

phone="0211234567"

print("Thisnumber:{}isamobilephone

number".format(phone))

10.4. Write good code that works!

print('"Python"isacoolprogramminglanguage')

print('MontyPythonisveryfunny.Youshouldwatchit!')

#Createvariables

first_name=input("Whatisyourfirstname?")

last_name=input("Whatisyourlastname?")

full_name=first_name+""+last_name

print("Yourfirstnameis:{},yourlastnameis:{}and

togetherthatmakesyou:{}".format(first_name,last_name,

full_name))

10.5. Review quiz time!

Review Quiz Questions:

1. print("All right ... all right ... but apart from better sanitation and

medicine and education and irrigation and public health and roads

and a freshwater system and baths and public order ... what have

the Romans ever done for us?")

2. print(4 + 2 * 4)

3. 7

4. fave_number = int(input("What is your favorite number?"))

11. Introduction to selection

11.1. Introduction to selection

name=input("Whatisyourname?")



ifname=="Bob":

print("That'saprettycoolname!")

else:

print("Notascoolasmyname!")



11.2. Understand how a condition works

print(4==9)

print("Bob"=="Bob")



#WriteaprintstatementthatevaluatestoTrue

print(5==5)



#WriteaprintstatementthatevaluatestoFalse

print("Oneofthesethings"=="Theothers")

11.3. Use different comparative operators

#Printstatementpractice

print(5<35)



print(3*3>4*4)



#Gettingsomeuserinput

number=int(input("Pickanumber"))



ifnumber<10:

print("Youpickedalownumber,lessthan10infact")

else:

print("Yournumberisgreaterthanorequalto10")

11.4. Use elif to make more options

number=int(input("Pickanumber:"))



ifnumber<=10:

print("That'sasmallnumber!")

elifnumber>10andnumber<=100:

print("That'samediumsizednumber")

else:

print("Wowthat'sbig!")

11.5. Review quiz on selection

Review Quiz Questions:

1. print(32 < 45)

2. <

3. >=

4. if age <= 12:

12. More selection options

12.1. Get to know the if statement a bit better

mood=input("Howareyoufeelingtoday?")



ifmood=="happy":

print("That'sgreat!")

12.2. Add a second if statement for more options

mood=input("Howareyoufeelingtoday?")



ifmood=="happy":

print("That'sgreat!")

ifmood=="sad":

print("Sorrytohearthat")

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12.3. Add a default response using else

#Asktheuserhowtheyfeel

mood=input("Howareyoufeelingtoday?")



#Printaresponsedependingontheirmood

ifmood=="happy":

print("That'sgreat!")

else:

print("Sorrytohearthat")

12.4. Adding more than one condition using elif

#Asktheuserhowtheyfeel

mood=input("Howareyoufeelingtoday?")



#Printaresponsedependingontheirmood

ifmood=="happy":

print("That'sgreat!")

elifmood=="sad":

print("Sorrytohearthat")

elifmood=="tired":

print("Youshouldgetanearlynight")

else:

print("Oh,really?")

12.5. Review quiz

Review Quiz Questions:

1. :

2. elif

4. It is indented

13. Boolean values and operators

13.1. Recognise and use > and < (greater than and less than)

13.2. Using and and or keywords

13.3. Use not - not ! but the other NOT...

13.4. Using operators with strings

13.5. Putting it all together

14. Matching strings

14.1. Take a closer look at the == operator

#Asktheuserfortheirname

name=input("Whatisyourname?")

#CheckifitisBobandreply

ifname=="Bob":

print("YournameisBob!")

else:

print("YournameisnotBob.")

14.2. Match strings using the == operator

#TheseprintstatementsprintTrue

print("sarah"=="sarah")

print("Pizzaisverycheesy"=="Pizzaisverycheesy")

#TheseprintstatementsprintFalse

print("Ni!"=="ni!")

print("LearntoCode;changetheworld"=="Learntocode;

changetheworld")

14.3. Match strings with spaces

#ThisshouldprintFalse

print("It'ssunnyoutsidetoday"=="It'ssunnyoutside

today")



#Youcanmatchstringvariableswithstringstoo

phrase="PythonwasinventedbyGuidovanRossum"



ifphrase=="PythonwasinventedbyGuidovanRossum":

print("YouknowyourPythonhistory!")



#MakethisprintTrue

print("TheGreenTreePythonisaround7feetlong"=="The

GreenTreePythonisaround7feetlong")

14.4. Deal with capitals and spaces

word=input("Enteraword:")



#Changingtolowercase

word=word.lower()

print(word)



#Stripspacesandprint

word=word.strip()

print(word)



#Changetotitlecaseandprint

word=word.title()

print(word)



#Changetouppercaseandprint

word=word.upper()

print(word)

14.5. Review quiz on comparing strings

Review Quiz Questions:

1. "Correct, you may enter!"

2. "SHRUBBERY"

3. "hering"

4. "Correct, you may enter!"

15. Numeric input in if statements

15.1. Use numeric input in if statements

#Asktheuserfortheirheight

height=int(input("Enteryourheightincm:"))



#Tellthemiftheyareshortortall

ifheight>165:

print("Youaretall")

else:

print("Youareshort")

15.2. Write an if/else statement using numbers

#Askuserhowlongtheyspendonline

internet_hours=int(input("Howmanyhoursdoyouspendon

theinterneteachday?"))



#Checkiftheyspendtoomuchtimeornot

ifinternet_hours<3:

print("That'sahealthyamountoftime")

else:

print("Youneedtogetmorefreshair!")



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15.3. Adding more branches with elif

#Askuserhowlongtheyspendonline

internet_hours=int(input("Howmanyhoursdoyouspendon

theinterneteachday?"))

#Checkiftheyspendtoomuchtimeornot

ifinternet_hours<3:

print("That'sahealthyamountoftime")

elifinternet_hours>=3andinternet_hours<=5:

print("Makesureyouarealsobeingactive.")

elifinternet_hours>5andinternet_hours<=24:

print("Youneedtogetmorefreshair!")

else:

print("Thereareonly24hoursinaday!")



15.4. Make comparisons between 2 stored values

#Setthecorrectanswerto9

ANSWER=9

#Asktheusertoguessthenumber

guess=int(input("WhatnumberamIthinkingof?"))

#Checkiftheyarerightornot

ifguess==ANSWER:

print("Correct!")

else:

print("Nope,youarewrong!")

15.5. Review Quiz

Review Quiz Questions:

1. int()

2. You are short

3. You are average sized

4. You are very short

5. WORLD_RECORD

16. Formatting your code

16.1. Write more good Python code!

ANSWER=9

#Askuserfortheirguess

guess=int(input("Guessanumber:"))

#Checkiftheyarecorrect

ifguess==ANSWER:

print("Youchose:{}".format(guess))

print("Analysing...")

print("Youarecorrect!")

else:

print("Youchose:{}".format(guess))

print("Youareincorrect...")

print("Betterlucknexttime!")

16.2. Use correct spacing and punctuation around conditions

weight=int(input("Howmuchdoesyourparcelweigh?"))

#Checktheweightvariable

ifweight>0andweight<=3:

print("Shippingwillcost$5")

elifweight>3andweight<=10:

print("Shippingwillcost$10")

else:

print("Contactusforaquote")

16.3. Use constants for values that are set or don't change

DELIVERY=10

PIZZA_PRICE=15



#Setvariableequaltoinput

num_pizzas=int(input("Howmanypizzasdoyouwant?"))



#Setvariabletopizzastimesprice

order_total=num_pizzas*PIZZA_PRICE



#ifpizzasarelessthan3

ifnum_pizzas<3:

print("Deliverywillcost${}".format(DELIVERY))

order_total+=DELIVERY

else:

print("Freedeliveryfor3ormorepizzas!")



#Print"Yourordercomesto:..."

print("Yourorderof{}pizzascomesto:

${}".format(num_pizzas,order_total))

16.4. Write useful comments

DELIVERY=10

PIZZA_PRICE=15



#Asktheuserhowmanypizzastheywantandstorevalue

num_pizzas=int(input("Howmanypizzasdoyouwant?"))



#Calculatecostoforder

order_total=num_pizzas*PIZZA_PRICE



#Checkwhetherorderqualifiesforfreedelivery

ifnum_pizzas<3:

print("Deliverywillcost${}".format(DELIVERY))

order_total+=DELIVERY

else:

print("Freedeliveryfor3ormorepizzas!")



#Displayordersummary

print("Yourorderof{}pizzascomesto:

${}".format(num_pizzas,order_total))

16.5. Review quiz

Review Quiz Questions:

1. if num_pizzas > 3 and num_pizzas < 10:

2. #Check shipping weight and add correct postage price

3. 1 tab

4. HOURS_WORKED

17. Formatting using an index

17.1. Use indices to format strings

print("Educationisthe{2}tounlockthegolden{0}of{1}.

‐GeorgeWashingtonCarver".format("door","freedom","key"))



word1="Knowledge"

word2="Wisdom"



print("{1}isknowingatomatoisafruit.{0}isnotputting

itinafruitsalad.".format(word2,word1))

17.2. Using an index more than once

print("Byallmeanslet'sbe{0},butnotso{0}thatour

brainsdropout.".format("open‐minded"))



print("WearenolongertheKnightswhosay\"{2}!\",weare

theKnightswhosay\"{1}‐{1}‐{1}‐{0}‐{3}‐

boing!\"".format("pitang","ekki","ni","zoom"))

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17.3. Store a string to be formatted in a variable

#Setupthesentenceskeleton

SENTENCE="I{}the{}{}"

#Askuserforwordstoputinsentence

verb=input("Pleaseenteraverb(doingword):")

adj=input("Pleaseenteranadjective(describingword):")

noun=input("Pleaseenteranoun(thing):")

#Printoutsentence.

print(SENTENCE.format(verb,adj,noun))

17.4. Format floats so they have the right number of decimal places

HOURLY_RATE=13.75

hours_worked=37.5

wages=HOURLY_RATE*hours_worked

print("Thisweekyouworked:{:.1f}

hours".format(hours_worked))

print("Youearned:${:.2f}beforetax".format(wages))

#Takeoff20%tax

wages*=0.8

#Addyourprintstatementhere

print("Aftertax:${:.2f}".format(wages))

17.5. Review quiz!

Review Quiz Questions:

1. 2

2. Why do people say 'no offense' right before they're about to offend

you?

3. print(lyric.format("eat", "apples", "bananas"))

4. {:.2f}

18. Debugging if statements

18.1. Bug hunt #2

score=10

#Askthenextquestion

answer=input("Whichmetalisheavier,silverorgold?")

answer=answer.strip().lower()

#Checkifansweriscorrectandaddorremovepoints

ifanswer=="gold":

print("Thatiscorrect,youget10points!")

score+=10

else:

print("Sorry,thatisincorrect,youlose2points")

score‐=2

print("Yourscoreisnow:{}points".format(score))

18.2. Indenting bugs

score=10



#Askthenextquestion

answer=input("Ganymedeisamoonofwhichplanet?")

answer=answer.strip().lower()



#Checkifansweriscorrectandaddorremovepoints

ifanswer=="jupiter":

print("Thatiscorrect,youget5points!")

score+=5

else:

print("Sorry,thatisincorrect,youlose3points")

score‐=3



print("Yourscoreisnow:{}points".format(score))

18.3. Greater... or less than? No... definitely greater. I think...

score=300



#Askthenextquestion

answer=int(input("Howmanybeesdoesittaketoequal

approximatelythesameweightasoneM&Mcandy?"))



#Checkifansweriscorrectandaddorremovepoints

ifanswer==10:

print("Thatiscorrect,youget100points!")

score+=100

elifanswer>10:

print("Theanswerwaslower!Youlose20points")

score‐=20

elifanswer<10:

print("Theanswerwashigher!Youlose20points")

score‐=20



print("Yourscoreisnow:{}points".format(score))

18.4. Spell those keywords right

score=30



#Askthenextquestion

answer=input("WhatisthenameofSaturn'slargestmoon?")

answer=answer.strip().lower()



#Checkifansweriscorrectandaddorremovepoints

ifanswer=="titan":

print("Thatiscorrect,youget10points!")

score+=10

elifanswer=="ganymede":

print("You'rethinkingofJupiter!Youlose5points")

score‐=5

else:

print("Sorry,incorrect,Youlose5points")

score‐=5



print("Yourscoreisnow:{}points".format(score))

18.5. Linking ifs with elses

score=30



#Askthenextquestion

answer=input("WhatisthenameofSaturn'slargestmoon?")

answer=answer.strip().lower()



#Checkifansweriscorrectandaddorremovepoints

ifanswer=="titan":

print("Thatiscorrect,youget10points!")

score+=10

elifanswer=="ganymede":

print("You'rethinkingofJupiter!Youlose5points")

score‐=5

else:

print("Sorry,incorrect,Youlose5points")

score‐=5



print("Yourscoreisnow:{}points".format(score))



19. Testing if statement conditions

19.1. Test if statements using ==

19.2. Testing if conditions with numbers

19.3. Test if statement conditions

19.4. Test more complex if statement conditions

19.5. Test boundary values in if statements

20. Review lessons 11-19

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20.1. Review the if statement

#Askuserforfavoriteicecreamflavor

fave_flavor=input("Whatisyourfavoriteflavorofice

cream?")

fave_flavor=fave_flavor.strip().lower()

iffave_flavor=="cookiesandcream":

print("Minetoo!")

20.2. Review quiz!

Review Quiz Questions:

1. >=

2. Either 3 > 2 or 9 < 6 or both must be true for x to be true

3. :

4. if time < 24 - 8:

20.3. Review if/else statements

#Asktheuserhowmanyservingsoffruitandvegestheyhave

had

servings=int(input("Howmanyservingsoffruitand

vegetableshaveyouhadtoday?"))

#Checkwhetherthey'vemetthehealthythreshold.

ifservings>=5:

print("Welldone,you'vehadyour5+today!")

else:

print("Youshouldeat5+aday,everyday.")

20.4. Conditions review quiz

Review Quiz Questions:

1. False

2. True

3. True

4. False

20.5. Review if/elif/else statements

#Asktheusertoratethelastmovietheywatched

rating=int(input("Ratethelastmovieyouwatchedoutof5

(1=bad,5=great):"))

#Checkwhetheritwasagoodmovieornot

ifrating==3:

print("Prettyaveragehuh?")

elifrating<3:

print("Wow,thatmusthavebeenbad!")

elifrating>3andrating<=5:

print("Soundslikeagreatmovie!")

else:

print("Isaidoutof5!")

21. Introduction to for loops

21.1. Introduction to loops

21.2. Meet the for loop

foriinrange(10):

print(i)

21.3. Customise a for loop

print("‐‐‐‐‐‐‐‐Loop1‐‐‐‐‐‐‐")



foriinrange(0,7):

print(i)



print("‐‐‐‐‐‐‐‐Loop2‐‐‐‐‐‐‐")



foriinrange(1,11):

print(i)



print("‐‐‐‐‐‐‐‐Loop3‐‐‐‐‐‐‐")



foriinrange(20,28):

print(i)



print("‐‐‐‐‐‐‐‐Yourloop‐‐‐‐‐‐‐")



foriinrange(5,18):

print(i)

21.4. Meet the while loop

i=1

whilei<=10:

print(i)

i+=1





21.5. Use other conditions in a while loop

#Setupthevariablethatwillruntheloop

response="no"



#Repeatloopuntilwearethere!

whileresponse!="yes":

response=input("Arewethereyet?")



print("Yay!")

22. Customising for loops

22.1. Use for loops for printing numbers

#Printnumbers0‐8

foriinrange(9):

print(i)



#Print"Iwillpracticecodingeveryday!"5times

foriinrange(5):

print("Iwillpracticecodingeveryday!")



#Giveyourself3cheers

foriinrange(3):

print("Hiphip...")

print("Hooray!")





22.2. Customising the start and end points

#Printnumbers1‐10

foriinrange(1,11):

print(i)



print()

#Printnumbers20‐35

foriinrange(20,36):

print(i)



print()

#Printnumbers9‐18inasentence

foriinrange(9,19):

print("Thenextnumberis{}".format(i))

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22.3. Customise the step

print("‐‐‐‐‐‐‐Loop#1‐‐‐‐‐‐‐‐")

foriinrange(0,20,2):

print(i)



print("‐‐‐‐‐‐‐Loop#2‐‐‐‐‐‐‐‐")

foriinrange(6,22,3):

print(i)

print("‐‐‐‐‐‐‐Loop#3‐‐‐‐‐‐‐‐")

foriinrange(10,0,‐1):

print(i)

print("‐‐‐‐‐‐‐Loop#4‐‐‐‐‐‐‐‐")

foriinrange(100,‐1,‐10):

print(i)

22.4. Using the i variable

#Print3timestable

foriinrange(1,13):

print("3x{}={}".format(i,i*3))

22.5. Review quiz!

Review Quiz Questions:

1. 4

2. 31

3. 35

4. 4 + 3 = 7

23. Refactoring turtle graphic loops

23.1. Refactor turtle code using loops

#Setupturtle

importturtle

tiny=turtle.Turtle()

tiny.pensize(5)

#Drawasquare

foriinrange(4):

tiny.forward(150)

tiny.right(90)

23.2. Use a list to run a for loop

#Setupturtle

importturtle

tiny=turtle.Turtle()

tiny.pensize(5)

#Makealistofcolors

colors=["red","yellow","blue","green"]

#Drawasquarewithonesideeachcolorusingaloop

forcolorincolors:

tiny.pencolor(color)

tiny.forward(150)

tiny.right(90)

23.3. Use loops to draw other shapes

#Setupturtle

importturtle

tiny=turtle.Turtle()

tiny.pensize(5)



#Gotoposition

tiny.penup()

tiny.goto(60,220)

tiny.pendown()



#Drawaredhexagon

tiny.pencolor("red")

foriinrange(6):

tiny.forward(100)

tiny.left(60)



#Gotoposition

tiny.penup()

tiny.goto(360,220)

tiny.pendown()



#Drawatrianglethathasabluelineandyellowfill

tiny.pencolor("blue")

tiny.fillcolor("yellow")



tiny.begin_fill()

foriinrange(3):

tiny.forward(100)

tiny.left(120)

tiny.end_fill()



#Gotoposition

tiny.penup()

tiny.goto(200,440)

tiny.pendown()



#Drawafilledpinkpentagon

tiny.pencolor("pink")

tiny.fillcolor("pink")



tiny.begin_fill()

foriinrange(5):

tiny.forward(100)

tiny.left(72)

tiny.end_fill()

23.4. Spirographs!

#Setupturtle

importturtle

spiro=turtle.Turtle()

spiro.color("blue")



#Drawaspirograph

foriinrange(100):

#Changecolors

ifi==20:

spiro.color("red")

elifi==40:

spiro.color("orange")

elifi==60:

spiro.color("yellow")

elifi==80:

spiro.color("green")



#Drawthespirograph

spiro.forward(200)

spiro.left(184)

spiro.forward(40)

spiro.right(30)



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23.5. Random numbers and RGB colors

#Setup‐alwaysdoallimportstogetheratthetopofyour

code

importrandom

importturtle

spiro=turtle.Turtle()

spiro.pensize(2)

spiro.goto(100,250)

#Changecolors

red=random.randrange(0,256)

green=random.randrange(0,256)

blue=random.randrange(0,256)

spiro.color((red,green,blue))

#Drawaspirograph

foriinrange(100):

spiro.forward(300)

spiro.left(184)



24. Complex for loop example

24.1. Working through an example

#Asktheuser'snameandgreetthem

name=input("Whatisyourname?")

print("Hello,{}!".format(name))

24.2. Create the for loop

#Asktheuser'snameandgreetthem

name=input("Whatisyourname?")

print("Hello,{}!".format(name))

#Asktheuserfornumberofhoursspentonlineforeachof

thepast7days

foriinrange(1,8):

hours=input("Howmanyhoursdidyouspendonlineonday

{}?:".format(i))

print(hours)

24.3. Adding up the total hours

#Asktheuser'snameandgreetthem

name=input("Whatisyourname?")

print("Hello,{}!".format(name))

total_hours=0

#Asktheuserfornumberofhoursspentonlineforeachof

thepast7days

foriinrange(1,8):

hours=float(input("Howmanyhoursdidyouspendonlineon

day{}?:".format(i)))

total_hours+=hours



print("Youspent{}hoursonlinein

total.".format(total_hours))

24.4. Finding the lowest number

#Asktheuser'snameandgreetthem

name=input("Whatisyourname?")

print("Hello,{}!".format(name))



total_hours=0

lowest_hours=None



#Asktheuserfornumberofhoursspentonlineforeachof

thepast7days

foriinrange(1,8):

hours=float(input("Howmanyhoursdidyouspendonlineon

day{}?:".format(i)))

total_hours+=hours



#Checkifcurrenthoursarethelowesthoursandstoreif

so

iflowest_hours==Noneorhours<lowest_hours:

lowest_hours=hours



print("Youspent{}hoursonlinein

total.".format(total_hours))

print("Theleasttimeyouspentonlineinonedaywas{}

hours".format(lowest_hours))

24.5. Review quiz!

Review Quiz Questions:

1. :

2. 13

3. 7

4. 19

25. Introduction to while loops

25.1. Get to know the while loop

#Printnumbers0‐8

i=0

whilei<9:

print(i)

i+=1



#Print"Iwillpracticecodingeveryday!"5times

i=0

whilei<5:

print("Iwillpracticecodingeveryday!")

i+=1



#Giveyourself3cheers

i=0

whilei<3:

print("Hiphip...")

print("Hooray!")

i+=1



25.2. Customise the start and stop points for a while loop

#Printnumbers1‐5

i=1

whilei<=5:

print(i)

i+=1



print()

#Printnumbers10‐25

i=10

whilei<=25:

print(i)

i+=1



print()

#Printnumbers9‐18inasentence

i=9

whilei<=18:

print("Thenextnumberis{}".format(i))

i+=1

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25.3. Customise the step in a while loop

print("‐‐‐‐‐‐‐Loop#1‐‐‐‐‐‐‐‐")

i=1

whilei<=128:

print(i)

i*=2



print("‐‐‐‐‐‐‐Loop#2‐‐‐‐‐‐‐‐")

i=6

whilei<=21:

print(i)

i+=3

print("‐‐‐‐‐‐‐Loop#3‐‐‐‐‐‐‐‐")

i=10

whilei>0:

print(i)

i‐=1

print("‐‐‐‐‐‐‐Loop#4‐‐‐‐‐‐‐‐")

i=100

whilei>=0:

print(i)

i‐=10

25.4. Using the i variable

#Print3timestable

i=1

whilei<=12:

print("3x{}={}".format(i,i*3))

i+=1

25.5. Review quiz

Review Quiz Questions:

1. 5

2. 31

3. 15

4. 0

26. Alternate loop counters

26.1. Run a while loop with a variable other than i

#Setacorrectanswer

ANSWER=9

#Givetheuser3lives

lives=3

#Givetheuser3triestoguessthenumber,andtellthem

whethertheyarecorrectornot

whilelives>0:

guess=int(input("GuesswhatnumberI'mthinkingof:"))



ifguess==ANSWER:

print("Correct!")

lives=0

else:

print("Wrong!")

lives‐=1

26.2. Run a while loop with user input

#Setamountofpocketmoney

pocket_money=40.00

#Asktheuserforthepriceofitemsuntiltheycan'tafford

anymore

whilepocket_money>0:

price=float(input("Howmuchdoyouwanttospendonthis

item?"))

pocket_money‐=price

print("Youhave${:.2f}left".format(pocket_money))

26.3. Use a Boolean variable to run a while loop

#Setamountofpocketmoney

pocket_money=40.00

still_shopping=True



#Asktheuserforthepriceofitemsuntiltheycan'tafford

anymore

whilestill_shopping==True:

price=float(input("Howmuchdoyouwanttospendonthis

item?"))

pocket_money‐=price

print("Youhave${:.2f}left".format(pocket_money))



#Checkiftheuserwantstopurchasemore

confirm=input("Wouldyouliketokeepshopping?")

ifconfirm=="no":

still_shopping=False

26.4. Use more complex conditions to run a while loop

#Setamountofpocketmoney

pocket_money=40.00

still_shopping=True



#Asktheuserforthepriceofitemsuntiltheycan'tafford

anymore

whilestill_shopping==Trueandpocket_money>0:

price=float(input("Howmuchdoyouwanttospendonthis

item?"))



#Checkiftheyhaveenoughforthatitem

ifpocket_money‐price>=0:

pocket_money‐=price

else:

print("Youcan'taffordthat.")



print("Youhave${:.2f}left".format(pocket_money))



#Checkiftheuserwantstopurchasemore

confirm=input("Wouldyouliketokeepshopping?")

ifconfirm=="no":

still_shopping=False

26.5. Use conditions to make sure input is within the right boundaries

#Askuserhowlongtheyhaveexercisedfortoday

time=int(input("Howmanyminutesofexercisedidyoudo

today?"))



#Ifaninvalidnumberisentered,repeatuntiltheyenterone

between0‐1440

whiletime<0ortime>1440:

print("Pleaseenteravalidnumber.Thetotalminutesin

onedayis1440")

time=int(input("Howmanyminutesofexercisedidyoudo

today?"))

27. Using break and continue

27.1. Use the break and continue statements with for loops

#Breakthisloopafter13isprinted

foriinrange(5,15):

print(i)

ifi==13:

break



print("‐‐‐‐‐")#Separatetheoutputfromthe2loops



#Makethisloopskipprinting9

foriinrange(12):

ifi==9:

continue

print(i)

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27.2. Using an else with a for loop

#Askuserforlogindetailsandgivethem3tries

PASSWORD="ekki‐ekki‐ekki"

foriinrange(3):

guess=input("Password:").strip().lower()

ifguess==PASSWORD:#Ifcorrect

print("Correct,authorisationcomplete.")

break

else:#Ifincorrect

print("Incorrect")



else:#Ifincorrect3times

print("Sorry,3incorrectguesses,youraccounthasbeen

locked.")

27.3. Use break with a while loop

#Forcetheusertochooseavalidoption

whileTrue:

answer=input("Trueorfalse?Sharksare

mammals.").strip().lower()

#Exitloopifuserhasenteredavalidanswer

ifanswer=="true"oranswer=="false":

break

else:#Tellthemtoenteravalidanswer

print("PleaseanswerwithTrueorFalse.")



#Goontocheckiftheywererightorwrong

27.4. Use try/except to force numerical input

#Forcetheusertoenteravalidnumber

whileTrue:

try:

height=float(input("Enteryourheightinmetres:"))

break

exceptValueError:

print("Pleaseenteravalidheightinmetrese.g.1.65")

27.5. Review quiz time!

Review Quiz Questions:

1. It skips the rest of the iterations (passes) through a loop, ending it

straight away

2. It skips the rest of the current iteration (pass) through the loop, but

then does the rest of the loop

3. 0 1 2 3 5 6 7 8

4. try and except

28. Testing for infinite loops

28.1. Testing expected values

#Asktheuserfornumberofhoursspentexercising,this

acceptsexpectdvalues

hours=float(input("Howmanyhoursdidyouspendexercising

today?:"))

print("Youspent{:.1f}hoursexercising

today.".format(hours))



28.2. Test boundary values

#Asktheuserfornumberofhoursspentexercising,this

acceptsexpectedvaluesandforcesreentryifboundaryor

invalidnumbers

hours=float(input("Howmanyhoursdidyouspendexercising

today?:"))

whilehours<0orhours>24:

print("Pleaseenteranumberbetween0and24")

hours=float(input("Howmanyhoursdidyouspend

exercisingtoday?:"))



print("Youspent{:.1f}hoursexercising

today.".format(hours))

28.3. Test invalid or exceptional values

#Asktheuserfornumberofhoursspentexercising,this

acceptsexpectedvalues

whileTrue:

try:

hours=float(input("Howmanyhoursdidyouspend

exercisingtoday?:"))

ifhours<0orhours>24:

print("Pleaseenteranumberfrom0‐24!")

else:

break

exceptValueError:

print("Pleaseenteravalidnumber!")





print("Youspent{:.1f}hoursexercising

today.".format(hours))



28.4. Other ways of testing input data

#Validatenameinputtoensurenamedoesnotcontainnumbers

whileTrue:

name=input("Whatisyourname?").strip()



ifname.isalpha():

print("Validname")

break



elifname.isnumeric():

print("Youenteredanumber,pleaseenteravalidname")



else:

print("Youenteredanamewithanumber,pleaseentera

validname")

28.5. Review quiz

Review Quiz Questions:

1. 4

2. 7

3. -1

4. three

29. Debugging loops

29.1. Bug hunt #3

#Printoutthenumbers1‐12withaforloop

foriinrange(1,13):

print(i)



#Printoutthenumbers5‐15withawhileloop

i=5

whilei<=15:

print(i)

i+=1

29.2. Laying out code correctly

#Givetheuser5triestoguessanumber

NUMBER=4

GUESSES=5



foriinrange(GUESSES):

print("Youhave{}guessesleft.".format(GUESSES‐i))

guess=int(input("Guessthenumber:"))



ifguess==NUMBER:

print("Yes!That'sright!")

break

else:

print("Wrong!")



else:

print("Outofguesses,theanswerwas{}!".format(NUMBER))

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29.3. Debug while loop conditions

#Asktheusertochooseanumberbetween1and10

number=int(input("Chooseanumberbetween1and10:"))

whilenumber<1ornumber>10:

print("Pleaseenteranumberbetween1and10!")

number=int(input("Chooseanumberbetween1and10:"))



print("Youchose:{}.".format(number))

29.4. Debugging unintentional infinite loops or loops that don't run

#Print"Imustdomyhomework!"10times

i=0

whilei<10:

print("Imustdomyhomework!")

i+=1



#Printthenumbers10to1countingdown

i=10

whilei>0:

print(i)

i‐=1

29.5. Debugging intentionally infinite loops!

#Asktheusertoenterthenumberofhourssleeptheygot

lastnight.Thisshouldacceptvaluesbetween0and24

inclusive,andforcetheusertore‐enteriftheyenter

invaliddata.

whileTrue:

try:

sleep_hours=float(input("Howmanyhourssleepdidyou

getlastnight?"))

ifsleep_hours<0orsleep_hours>24:

print("Youcan'tsleepnegativehours,ormorethan24

hoursinoneday!")

else:

break

exceptValueError:

print("Pleaseenteranumber.")

#Checkiftheyaregettingenoughsleep

ifsleep_hours>=12:

print("Wow,that'salotofsleep!")

elifsleep_hours<12andsleep_hours>=8:

print("Yougotenoughsleeplastnight")

else:

print("Youshouldtrytogetmoresleep!")

30. Review lessons 21-29

30.1. Review loops

#Forloop

foriinrange(2,19):

print(i)



#Whileloop

i=2

whilei<=18:

print(i)

i+=1

30.2. Loops review quiz

Review Quiz Questions:

1. for i in range(3, 8):

2. for i in range(7):

3. i += 2

4. When you know how many times you want something to repeat

5. When you don't know how long it will take to get to the end point of

the loop

30.3. Review using the i variable

#Askusertoentersleepdataforday1throughtoday7

foriinrange(1,8):

hours_sleep=int(input("Enterhoursofsleeponday{}:

".format(i)))

print("Hoursofsleeponday{}:{}".format(i,

hours_sleep))



#Printout1‐3timestables

foriinrange(1,4):

forjinrange(1,4):

print("{}x{}={}".format(i,j,i*j))





30.4. Another review quiz!

Review Quiz Questions:

1. It counts up from -3 to 15 in 3s

2. A variable that stores a value which is either True or False

3. A square with sides 100px long

4. A hexagon

30.5. Review writing for and while loops that depend on user input

#Forloop

maximum=int(input("Pickanumber:"))



foriinrange(0,maximum):

print(i)



#Whileloop

answer=input("Whatisthecoolestprogramminglanguage?

").strip().lower()



whileanswer!="python":

answer=input("Whatisthecoolestprogramminglanguage?

").strip().lower()



