Cod sursa(job #1999928)

Utilizator lupulescu2001Lupulescu Vlad lupulescu2001 Data 12 iulie 2017 13:13:53
Problema Aria Scor 10
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
ifstream fin("aria.in");
ofstream fout("aria.out");
double s,x[100003],y[100003];
int main()
{
    int n,i;
    fin>>n;
    for(i=1;i<=n;i++)
        fin>>x[i]>>y[i];
    x[n+1]=x[1];
    y[n+1]=y[1];
    for(i=1;i<=n;i++)
        s=s+(x[i]*y[i+1]-x[i+1]*y[i])/2;
    fout<<s;
}