if???

if???????????????????? ??? ??????棬????????????????? if-?? ???? ???? ???????????????????? else-?? ???? else ??????????

???if???

??6.1 ???if???

#!/usr/bin/python
# Filename: if.py

number = 23
guess = int(raw_input('Enter an integer : '))

if guess == number:
    print 'Congratulations, you guessed it.' # New block starts here
    print "(but you do not win any prizes!)" # New block ends here
elif guess < number:
    print 'No, it is a little higher than that' # Another block
    # You can do whatever you want in a block ...
else:
    print 'No, it is a little lower than that'
    # you must have guess > number to reach here

print 'Done'
# This last statement is always executed, after the if statement is executed

????????code/if.py??

???

$ python if.py
Enter an integer : 50
No, it is a little lower than that
Done
$ python if.py
Enter an integer : 22
No, it is a little higher than that
Done
$ python if.py
Enter an integer : 23
Congratulations, you guessed it.
(but you do not win any prizes!)
Done

????ι???

??????????У???????????????2?????????????????????????????е??????????????number???????????????κ????????????????????23????????????raw_input()???????????2??????????????????????Ρ???????????????????????????????

??????????raw_input???????????????????????????????????????????????????????????????Щ?????????????????????????????????raw_input??????????????????????????int???????????????????????????洢?????guess?С???????int?????????????????????????????????????????????????????????????????????????????Ч????????????????

??????????????????2??????????????????????????????????????????????????????????????????????????Python??????????????????顣??????????????Python????????????????????????????????????????????????????????????

???if??????β?????????e??????????????????Python?????????????顣

??????????2????С?????????????????????????????????????2???????????????????????elif??????????????????????if else-if else?????????if-elif-else???????ó?????????????????????????????????

elif??else?????????????н?β???????e?????????????????????饗??????????????????????

????????????if??????????????if??????????????????if???

?????elif??else?????????????????????Чif??????

if True:
    print 'Yes, it is true'

??Python??????????????if?????????????????elif??else????????????if???????????????????????У?????????????顣????????????У?????????????print 'Done'??????????Python??????????β????????????С?

???????????????????????????????????????????????????????????????????????Щ??????????????????????Щ???C/C++????????????????????????????????????????????????????????????е???????????????

??C/C++??????????
??Python?????switch???????????if..elif..else?????????????????????Щ?????????????????????