Cod sursa(job #2837922)
Utilizator | Data | 22 ianuarie 2022 21:12:00 | |
---|---|---|---|
Problema | Aria | Scor | 10 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.43 kb |
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("aria.in");
ofstream fout("aria.out");
const int MAX=1e5+5;
struct punct
{
long double x,y;
}v[MAX];
int n;
long double aria;
int main()
{
fin >> n;
for(int i=1;i<=n;i++)
fin >> v[i].x >> v[i].y;
v[n+1]=v[1];
for(int i=1;i<=n;i++)
aria+=v[i].x*v[i+1].y-v[i+1].x*v[i].y;
fout << aria/2.0;
return 0;
}