Cod sursa(job #2683562)
Utilizator | Data | 11 decembrie 2020 16:52:46 | |
---|---|---|---|
Problema | Aria | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 0.47 kb |
#include <iostream>
#include <fstream>
#include <iomanip>
using namespace std;
ifstream f ("aria.in");
ofstream g ("aria.out");
int n;
long double arie;
struct punct{
long double x;
long double y;
};
punct p[100010];
int main(){
f>>n;
for(int i=1; i<=n; i++){
f>>p[i].x>>p[i].y;
}
p[n+1]=p[1];
for(int i=1; i<=n; i++)
arie+=(p[i].x*p[i+1].y - p[i+1].x*p[i].y)/2;
g<<fixed<<setprecision(5)<<arie;
return 0;
}