pointer practice (decomposing fraction program)

#include <stdio.h>

void decompose();

int main(void)
{
    long i;
    double d;
    decompose(3.141592, &i, &d);
    
    printf("%ld\n", i);
    printf("%lf", d);
}

void decompose(double x, long *int_part, double *frac_part)
{
    *int_part = (long) x;
    *frac_part = x - *int_part;
}