c - How is i==(20||10) evaluated?

Question

#include <stdio.h>
int main(void)
{
   int i=10;
   if(i==(20||10))
       printf("True");
   else
       printf("False");
   return 0;
}

This gives the output False.

Please explain to me how does this program work?

Answer 1

This line if(i==(20||10)) always evaluates to i==1 as Alk said in comments - (20||10) evaluates to 1, hence when you compare i == 1, that is why you get False as the output. A non-Zero value in C implies true.

Read about Short-circuit evaluation

Perhaps this is what you wanted:

int i=10;
if(i==20 || i == 10)
    printf("True");
else
    printf("False");