Cod sursa(job #1584620)
Utilizator | Nisioi Ciprian CipiNis | Data | 30 ianuarie 2016 12:24:32 |
---|---|---|---|
Problema | Aria | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.47 kb |
#include <fstream>
#include <iomanip>
#define DIM 100002
using namespace std;
ifstream f("aria.in");
ofstream g("aria.out");
struct punct
{
double x,y;
}v[DIM];
int n;
double arie;
int main()
{
f>>n;
for(int i=1;i<=n;++i){
f>>v[i].x>>v[i].y;
}
v[n+1]=v[1];
for(int i=1;i<=n;++i){
arie+=(v[i].x*v[i+1].y-v[i+1].x*v[i].y);
}
g<<fixed<<setprecision(5)<<arie/2;
f.close();
g.close();
return 0;
}