C++ for loop question

Question

int x=1;
for (int i=3; i<5; i++){
x+=i;
why it is 8, does anybody know it?

Answer 1

x starts at 1 (x=1)

i starts at 3 (int i = 3)

x += i means take the value of i, add it to x, then assign that value back into x. So with x = 1 and i = 3, 1 + 3 = 4

Increment i by one so now it is at 4.

Same as above, now x is 4 and i is 4, so 4 + 4 = 8

increment i so now it is 5

The loop condition is now broken, so the loop exits.

Answer 2

Thanks a lot man!