ceiling function

gistfile1.c

#include <stdio.h>

double my_ceil(double x) {
    double y = (double) ((long long) x);
    if (x - y == 0) {
        return x;
    } else {
        if (x > 0) {
            return y + 1;
        } else {
            return y;
        }
    }
}

int main(void) {
  printf ("ceil of 2.0 is %.1lf\n", my_ceil(2.0) );
  printf ("ceil of 3.8 is %.1lf\n", my_ceil(3.8) );
  printf ("ceil of -2.3 is %.1lf\n", my_ceil(-2.3) );
  printf ("ceil of -3.0 is %.1lf\n", my_ceil(-3.0) );

  return 0;
}