Cod sursa(job #1435709)
Utilizator | Cella Florescu cella.florescu | Data | 14 mai 2015 09:57:38 |
---|---|---|---|
Problema | Aria | Scor | 70 |
Compilator | c | Status | done |
Runda | Arhiva educationala | Marime | 0.52 kb |
#include <stdio.h>
#include <stdlib.h>
struct poligon{
double x, y;
} v[100001];
int main()
{
FILE *fin, *fout;
int n, i;
double arie;
fin=fopen("aria.in", "r");
fscanf(fin, "%d", &n);
for(i=0; i<n; i++)
fscanf(fin, "%lf%lf", &v[i].x, &v[i].y);
fclose(fin);
v[n]=v[0];
arie=0.0;
for(i=0; i<n; i++)
arie+=v[i].x*v[i+1].y-v[i+1].x*v[i].y;
fout=fopen("aria.out", "w");
fprintf(fout, "%lf", fabs(arie/2.0));
fclose(fout);
return 0;
}