Cod sursa(job #2233846)
Utilizator | Data | 24 august 2018 16:06:05 | |
---|---|---|---|
Problema | Aria | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.38 kb |
#include <bits/stdc++.h>
using namespace std;
ifstream f("aria.in");
ofstream g("aria.out");
const int N=100010;
double x[N],y[N],A;
int n;
int main()
{
f>>n;
for(int i=1;i<=n;i++)
f>>x[i]>>y[i];
x[0]=x[n];
y[0]=y[n];
for(int i=0;i<n;i++ )
A+=(y[i]+y[i+1])*(x[i]-x[i+1])/2.0;
g<<fixed<<setprecision(10)<<A;
return 10;
}