I don't know why my code is rejected. Can anyone say why?

Question

#include<iostream>
using namespace std ;
int main ()
{int i=20;
cout<<i++<<i++<<i++;
cout<<i;
return 0;
}

Answer 1

Your quiz submission was rejected because multiple prefix/postfix operators used on a single variable between two sequence points will result in undefined behaviour.

https://stackoverflow.com/questions/4176328/undefined-behavior-and-sequence-points

Answer 2

i wonder who is teaching ppl these methods. i mean even if this code didnt result in undefined behaviour, what possible usage would it have in a program?

Answer 3

@Jay Obfuscation? :D

Answer 4

The code is correct. Make sure you saved it as .cpp and not .c

Happened to me a few times in rush