Returning more than one value at a time from a function in C program

PROGRAM:

#include <stdio.h>
void circle(int,float *,float *);
int main()
{
    int radius;
    float area,perimeter;
    scanf("%d",&radius);
    circle(radius,&area,&perimeter);
    printf("\nArea=%f\nPerimeter=%f\n",area,perimeter);
    return 0;
}
void circle(int r,float *a,float *p)
{
    *a=3.1416*r*r;
    *p=2*3.1416*r;
}

OUTPUT:
5
Area=78.500000
Perimeter=31.400000