Cod sursa(job #2738700)
Utilizator | Dragan Andrei AndreiD31 | Data | 6 aprilie 2021 11:26:43 |
---|---|---|---|
Problema | Aria | Scor | 70 |
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");
struct
{
double x,y;
}v[100100];
int n,i;
double aria;
int main()
{
f>>n;
for(i=1;i<=n;i++)f>>v[i].x>>v[i].y;
for(i=2;i<=n;i++)aria=aria+(v[i-1].x*v[i].y-v[i-1].y*v[i].x);
aria=aria+(v[n].x*v[1].y-v[n].y*v[1].x);
aria=aria/2;
g<<fixed<<setprecision(5)<<aria;
return 0;
}