Python Loops

Loops are for repetitive operations

# Example Loops
# this loop from 0 to 99
for i in range (100):
    print ( i )

# range (a,b) will loop from a to b
#   and a must be less than b
for i in range (3,5):
    print ( i )

# What is 3 doing here? Three is a crowd, or not?
for i in range (10,20,3):
    print ( i )

# Break or continue? That is the question.
for i in range ( 0, 9 ):
    if ( i == 7 ): break
    if ( i % 2 == 0 ): continue

# Lazy Ann's version
for i in range(10):
    if i == 7: break
    if i%2: continue

# Look! I can do days too!
days = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat" ]
for d in days:
    print ( d )

# Python has while loop too.
i = 0
while i < 3:
    print ( i )
    i += 1
 
## Remember, python does not do "i++"

while True:
    print ( "I am in loop!" )
    if True:
        break
## See? You have to break it otherwise it goes on and on and on...

# No, python does not have do while loop

# But it has something cool called 'enumerator'
for i, d in enumerate (days):
    print (i, d)

# descinding
for i in range (9,1,-1):
    print (i)

x = range(10)
z = list(range(10))
y = list( 10-i for i in x )
print (x)
print (z)
print (y)