Cod sursa(job #2592286)
Utilizator | Data | 1 aprilie 2020 15:33:25 | |
---|---|---|---|
Problema | Aria | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.42 kb |
#include <bits/stdc++.h>
using namespace std;
ifstream f("aria.in");
ofstream g("aria.out");
int n;
struct puncte{
long double x , y;
}v[100005];
long double arie = 0;
int main()
{
f>>n;
for(int i=1;i<=n;i++){
f>>v[i].x>>v[i].y;
}
v[n+1].x=v[1].x;
v[n+1].y=v[1].y;
for(int i=1;i<=n;i++){
arie+= v[i].x * v[i + 1].y - v[i + 1].x * v[i].y;
}
arie/=2;
g << setprecision(6) << fixed << arie << '\n';
}