Increment and Decrement in Python-CodePudding

Is the increment/decrement step comes after/before the print function

my_list=[1,2,3,4,5,6,7,8,9]
sum=0
index=0
while sum<10:
    sum =my_list[index]
    index =1
    print(sum)

CodePudding user response：

The body of the while is executed from top to bottom. You first tried to increment the value of sum by the value of the first index of the my_list then you printed the sum. If you want to see the 0 as your first output, you have to do the printing first.

my_list = [1, 2, 3, 4, 5, 6, 7, 8, 9]
sum = 0
index = 0
while sum < 10:
    print(sum)
    sum  = my_list[index]
    index  = 1

output:

Also do not use built-in names(here sum) as your variable names.

CodePudding user response：

It doesn't matter. Why? You increment the index for the NEXT run, in the current run you don't need it anymore (you don't need it in the current run after sum =my_list[index]. Either way, you start with the index 0 and your first sum is 1 (0 1).