Cod sursa(job #2328585)
Utilizator | Lup Lucia Fredy | Data | 25 ianuarie 2019 22:31:12 |
---|---|---|---|
Problema | Aria | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.57 kb |
#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;
ifstream fin("aria.in");
ofstream fout ("aria.out");
#define limn 100010
struct {long double x,y;} points[limn];
int n;
long double aria(0);
int main()
{
fin>>n;
for (int i=0; i<n; i++)
fin>>points[i].x>>points[i].y;
points[n] = points[0];
for (int i=0; i<n; i++)
aria += (points[i].x*points[i+1].y - points[i].y*points[i+1].x);
fout<<setprecision(5)<<fixed<< (long double)aria/2.0;
fin.close();
fout.close();
return 0;
}