c - What is the effect of x=x++;? -


this question has answer here:

#include <stdio.h>  int main() {   int x=100;   x=x++;   printf("x : %d\n",x); //prints 101   return 0; }

what reason output 101? think output should 100.

this undefined behaviour, due sequence points.

between consecutive "sequence points" object's value can modified once expression

the end of previous epxression x=100; 1 sequence point, , end of x=x++; another.

basically, expression has no intermediate 'sequence points', yet you're modifying value of x twice. result of undefined behaviour: basically, anything happen: 100, 101 or 42...


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