Cod sursa(job #3214943)
Utilizator | Data | 14 martie 2024 16:21:50 | |
---|---|---|---|
Problema | Aria | Scor | 0 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.55 kb |
#include <fstream>
#include <vector>
#include <queue>
#include <iomanip>
using namespace std;
using pii = pair<int,int>;
ifstream cin("aria.in");
ofstream cout("aria.out");
int n , a , b , c , d;
double area;
signed main()
{
cin >> n;
n--;
cin >> a >> b;
int oga = a , ogb = b;
for(int i = 1 ; i <= n ; ++i)
{
cin >> c >> d;
area += a*d - c*b;
a = c;
b = d;
}
area += a*ogb - b*oga;
area /= 2;
cout << fixed << setprecision(5) << area << '\n';
return 0;
}