loop_list_tuple_dictionary.py

#! /usr/bin/python3
# ==================================================================
#
# Notes:
#
#-------------------------------------------------------------------
# The difference between a for loop and a while loop:
#
# Loops are used for repeating sections of code. Unlike a for
# loop, the while loop will not run n times. While loops run
# until a defined condition is no longer met. If the condition
# is initially false, the loop body will not be executed at all.
#
# ------------------------------------------------------------------
# Using else Statement with Loops:
#
# Python supports to have an else statement associated with a
# loop statement
#
#  - If the else statement is used with a for loop, the else
#    statement is executed when the loop has exhausted iterating
#    the list.
#
#  - If the else statement is used with a while loop, the else
#    statement is executed when the condition becomes false.
#
# ==================================================================

# lx   list
# tx   tuple
# dx   dictionary
# sx   string

lx = ['a','b','c','d','e']
tx = ('aa','bb','cc')
dx = { 'A':'aaa','B':'bbb','C':'ccc'}
sx = 'abcdef'

print('-----string-------------------------------------------')

l = len(sx)
print('sx length is ',l, '   type is ',type(sx))

for c in sx:
    print(c)

for idx,c in enumerate(sx):
    print(idx,c)

print('-----list---------------------------------------------')

l = len(lx)
print('lx length is ',l, '   type is ',type(lx))

for x in lx:
    print(x)

for idx,x in enumerate(lx):
    print(idx,x)

print('-----tuple--------------------------------------------')

l = len(tx)
print('tx length is ',l, '   type is ',type(tx))

for x in tx:
    print(x)

for idx,x in enumerate(tx):
    print(idx,x)

print('-----dictionary---------------------------------------')

# note:
# python3 - use dx.items()
# python2 - use dx.iteritems()

l = len(dx)
print('dx length is ',l, '   type is ',type(dx))

for k in dx:
    print('key=',k,'  value=',dx[k])

for k,v in dx.items():
    print(k,v)

print('-----loop else----------------------------------------')

print('for loop example')
for i in range(4):
    print(i)
else:
    print('end of for loop, i=',i)
print('while loop example')
i = 97
while i < 100:
    print(i)
    i += 1
else:
    print('end of while loop, i=',i)