Cod sursa(job #1669997)
Utilizator | Data | 31 martie 2016 12:47:09 | |
---|---|---|---|
Problema | Aria | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.41 kb |
#include <fstream>
using namespace std;
ifstream f("arie.in");
ofstream g("arie.out");
int n,i;
double arie,puncte[2][100001];
int main()
{
f>>n;
for(i=1;i<=n;i++)
f>>puncte[0][i]>>puncte[1][i];
puncte[0][0]=puncte[0][n];
puncte[1][0]=puncte[1][n];
for(i=0;i<n;i++)
arie=arie+(puncte[0][i]*puncte[1][i+1]-puncte[0][i+1]*puncte[1][i]);
g<<arie/2.0;
return 0;
}