modular multiplication in c

modmul.c

/*

gcc --ffast-math -std=c99 -o modmul modmul.c -lm
./modmul
(2 x 3) mod 6 = 0

*/

#include <stdio.h>

int modular_multiplication(int a, int b, int m) {
    return (a * b) % m;
}

int main(void) {
    int a = 2, b = 3, m = 6;
    int result = modular_multiplication(a, b, m);
    printf("(%d x %d) mod %d = %d\n", a, b, m, result);

  return 0;
}