Cod sursa(job #2306341)

Utilizator AlexPascu007Pascu Ionut Alexandru AlexPascu007 Data 22 decembrie 2018 01:32:35
Problema Aria Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include <fstream>
#define x first
#define y second
using namespace std;
ifstream fin("aria.in");
ofstream fout("aria.out");
int n,i,ans;
pair<int,int> v[100010];
int main() {
	fin>>n;
	for (i=1;i<=n;i++)
		fin>>v[i].x>>v[i].y;
	v[n+1]=v[1];
	for (i=1;i<=n;i++)
		ans+=(v[i].x*v[i+1].y-v[i+1].x*v[i].y)/2;
	fout<<ans;
	return 0;
}