Why this thing happens?Explain it guys.

Question

Guess the output and then run this snippet and plz explain why this thing is happning?
https://code.sololearn.com/cYbWV0ZoDSGC/?ref=app

Answer 1

in post increment value is first store then increment so here
i=87;
i=i++;
so the value due to post increment first uses the value of i then increment so
i=87
if you do i=++i then value first increment then use and i=88
https://www.sololearn.com/Discuss/407846/?ref=app

Answer 2

But According to Logic first i is assigned by 87 then it must be incremented by post increment operator...But this does not happen..

What I think is,it is due to the CPU registers where the statement executes...
it stores the value of i in a register and puts in again to the memory address of i hence the assignment value does not change..because increment to i has been overwritten by assigning previous value.