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Question

……
int x=8;
int y=7;
x++;
x+=y--;
why the value of final x is16 not 9+6=15
Can anyone show me the calculating process,thanks.

Answer 1

Because y will only be decremented after the assignment. x = y-- means: assign the value of y to x and decrement y afterwards. x = --y means: decrement y first and then assign the new value to x. So you would be correct if the code said x += --y.