#include<iostream>
#include<cstdio>
using namespace std;
int main(){
    double a,b,c,x;
    cin>>a>>b>>c;
    if(a+b>c&&b+c>a&&a+c>b){
        x=a+b+c;
        printf("Perimetro = %.1lf",x);
    }
    else{
        x=(a+b)*c/2;
        printf("Area = %.1lf",x);
    }
    return 0;
}