P27Loops

 

Loop through a collection

for name in ['christopher','susan',str(10),int(1000),float(1)]:
    print(name)

how do i then loop x number of times? The way you do that is by using a built-in little function called range. range will do for you is it will automatically create a list of numbers for you. 

Looping a number of times

for index in range(1,6):
    print(index)

 Looping with a condition

a = input('what you want to do ?')
name = ['na','bi','ss',a]
index = 1
while index < len(name):
    print(name[index]) 
    index = index + 1 #change the condition!!

 Typically you would want to use a while loop in situations where something is going to change automatically. So if I was maybe reading through a list of lines, inside of a file or someting like that, that's perfect for a while loop.

 

P28实操

people = ['Christopher','Susan']
for name in people:
    print(name)
print()
index = 0
while index < len(people):
    print(people[index])
    index = index + 1

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