Cod sursa(job #1902476)
Utilizator | tudoras8 tudoras8 | Data | 4 martie 2017 17:04:09 |
---|---|---|---|
Problema | Aria | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.6 kb |
#include <iostream>
#include <fstream>
#include <vector>
using namespace std;
int n;
vector<pair<double, double>> v;
int main(int argc, const char * argv[]) {
ifstream cin("aria.in");
ofstream cout("aria.out");
cin >> n;
for (int i = 0; i < n; i++) {
double x, y;
cin >> x >> y;
v.push_back({x, y});
}
int ans = 0;
for (int i = 0; i < n; i++) {
double aria = v[i].first * v[(i + 1) % n].second
- v[(i + 1) % n].first * v[i].second;
ans += aria;
}
ans /= 2;
cout << ans;
return 0;
}