Cod sursa(job #1921594)
Utilizator | Pantea Beniamin bt.pantea | Data | 10 martie 2017 13:24:33 |
---|---|---|---|
Problema | Aria | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.5 kb |
#include <fstream>
#include <cstdio>
#include <cmath>
using namespace std;
ifstream f ("aria.in");
pair < double, double > v[100001];
int n;
double sol;
int main()
{
f>>n;
freopen("aria.out", "w", stdout);
for(int i = 0; i < n; i++)
f>>v[i].first>>v[i].second;
v[n] = v[0];
for (int i = 0; i < n; i++)
sol += (v[i].first * v[i + 1].second - v[i].second * v[i + 1].first);
//g << fabs(sol / 2.0);
printf("%lf", fabs(sol / 2.0));
return 0;
}