HW2ex1

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

double setVars(double* a, double* b, double* c, double* S, double* P) {
    double semi;
    if(*a > 0 && *b > 0 && *c > 0) {
        *P = *a + *b + *c;
        semi = *P / 2;
        *S = sqrt(semi*(semi-*a)*(semi-*b)*(semi-*c));
        return 0;
    }
    return 2;
}

int main() {
    double a, b, c;
    double S = 0;
    double P = 0;

    while(scanf("%lf %lf %lf", &a, &b, &c) != EOF) {
        if(setVars(&a, &b, &c, &S, &P) == 0) {
            printf("S: %lf cm2\n", S);
            printf("P: %lf cm\n", P);
        } else {
            fprintf(stderr, "Invalid triangle sizes\n");
        }
    }

    return 0;

}