If you are trying to run modulo / remainder operator like below, there are higher chances you might get an error as “error: invalid operands to binary” The solution for this error is as mentioned below.

$ vim using_mod.c

#include <stdio.h>
int main(void) {
float num = 11.00;
int remainder = num % 3.0;
if (remainder == 0) {
printf("number is divisible\n");
} else {
printf("number is not divisible: Remainder = %d\n", remainder);
}
return 0;
}

$ gcc using_mod.c
using_mod.c: In function ‘main’:
using_mod.c:5:22: error: invalid operands to binary % (have ‘float’ and ‘double’)
int remainder = num % 3.0;

**Solution** : The remainder operator (otherwise known as the modulo operator) % is a binary operator (i.e., takes exactly 2 operands) and operates only on integer types (e.g., short, int, long, long long, etc).

Hence, we either need to change float to int, or typecast both the values before and after % operator. like

int remainder = (int)num % (int)3.0;

The complete working program will look like as below,

$ vim using_mod.c

#include <stdio.h>
int main(void) {
float num = 6.00;
int remainder = (int)num % (int)3.0;
if (remainder == 0) {
printf("number is divisible\n");
} else {
printf("number is not divisible: Remainder = %d\n", remainder);
}
return 0;
}

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