remainder()

remainder.c

#include <stdio.h>
#include <math.h>

int main(void) {
  double const number = 8.0;

  for (double i = number; i < number * 2 + 1; ++i) {
    printf("remainder(%2.0f, %2.0f) = %2.0f\n", i, number, remainder(i, number));
  }

  return 0;
}

/* output:

remainder( 8,  8) =  0
remainder( 9,  8) =  1
remainder(10,  8) =  2
remainder(11,  8) =  3
remainder(12,  8) = -4
remainder(13,  8) = -3
remainder(14,  8) = -2
remainder(15,  8) = -1
remainder(16,  8) =  0

*/