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c++ccompiler-constructionoperatorsequals-operator

Two '==' equality operators in same 'if' condition are not working as intended


I am trying to establish equality of three equal variables, but the following code is not printing the obvious correct answer which it should print. Can someone explain, how the compiler is parsing the given if(condition) internally?

#include<stdio.h>
int main()
{
        int i = 123, j = 123, k = 123;
        if ( i == j == k)
                printf("Equal\n");
        else
                printf("NOT Equal\n");
        return 0;
}

Output:

manav@workstation:~$ gcc -Wall -pedantic calc.c
calc.c: In function ‘main’:
calc.c:5: warning: suggest parentheses around comparison in operand of ‘==’
manav@workstation:~$ ./a.out
NOT Equal
manav@workstation:~$

EDIT:

Going by the answers given below, is the following statement okay to check above equality?

if ( (i==j) == (j==k))

Solution

  •   if ( (i == j) == k )
    
      i == j -> true -> 1 
      1 != 123 
    

    To avoid that:

     if ( i == j && j == k ) {
    

    Don't do this:

     if ( (i==j) == (j==k))
    

    You'll get for i = 1, j = 2, k = 1 :

     if ( (false) == (false) )
    

    ... hence the wrong answer ;)