rectangle

#include <stdio.h>

int rectangle(double w, double h, double *P, double *S){
    if(w <= 0 || h <= 0){
    return -1;
}
    *P = 2 * (w + h);
    *S = w * h;
    return 0;
}

int main(){
double a, b, P, S;
while(scanf("%lf %lf", &a, &b) != EOF){
    if(rectangle(a, b, &P, &S) == -1){
        fprintf(stderr, "Invalid rectangle sides!\n");
    }else{
        printf("S = %.2lf", S);
        printf("P = %.2lf", P);
    }
}
    return 0;
}