Guys explain to me about increment and decrement

Question

.
.
Int x=7;
Int y=4;

Cout<<x++ * y--;

// how is the out put 28??????

Answer 1

there is an order for these actions
if you do:
int x = 5;
cout << x++ + 5;
you will see 10, because 5 + 5 = 10, but after this line, x is now 6.

if you want the increment to happen first, you can use ++x

cout << ++x + 5;
now you will see a different result 11.

Answer 2

cout<<x++ * y--;
x++ return 7 but the value of x is now 8
y-- return 4 but the value of y is now 3
So 7*4 output become 28

Answer 3

10 q guys its all clear now Apollo-Roboto Mihir Lalwani

Answer 4

7*4 = 28, so the output is 28.

postcrement is implemented like this:

int post_add(int* x){
auto tmp = *x;
*x = (*x)+1;
return tmp;
}

you see the incremented value gets used at no time here.
But be careful how you use post and precrements especially as arguments to functions. There is many strange undefined behaviour to when what get's evaluated. (cppcast did a good episode on that)