Cod sursa(job #1857717)
Utilizator | Ahmed Hamza Aydin OFY4 | Data | 26 ianuarie 2017 16:08:09 |
---|---|---|---|
Problema | Aria | Scor | 10 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.54 kb |
#include <fstream>
using namespace std;
ifstream in("aria.in");
ofstream out("aria.out");
const int Max = 100007;
struct yer
{
double x, y;
}v[Max];
double formul(int n)
{
double sum = 0;
for(int i = 1; i <= n; ++i)
{
sum+= v[i].x * v[i + 1].y - v[i + 1].x * v[i].y;
}
return sum / 2;
}
int main()
{
int n;
in >> n;
for(int i = 1; i <= n; ++i)
{
in >> v[i].x >> v[i].y;
}
v[n + 1].x = v[1].x;
v[n + 1].y = v[1].y;
out << formul(n);
}