Cod sursa(job #317083)

Utilizator andreioneaAndrei Onea andreionea Data 22 mai 2009 15:35:45
Problema Poligon Scor 0
Compilator c Status done
Runda Arhiva de probleme Marime 0.56 kb
#include<stdio.h>
int x[801],y[801],n;
int main()
{FILE *f=fopen("poligon.in","r"),*g=fopen("poligon.out","w");
 int m,xx,yy,np=0,i,j;
  long a1=0,b;
 fscanf(f,"%d %d\n",&n,&m);
 for(i=1;i<=n;++i) fscanf(f,"%d %d\n",&x[i],&y[i]);
 for(i=2;i<n;++i) 
 a1+=(x[i]-x[1])*(y[i+1]-y[1])-(x[i+1]-x[1])*(y[i]-y[1]); 
 for(i=1;i<=m;++i)
	{fscanf(f,"%d %d\n",&xx,&yy);
	 b=0;
	 for(j=1;j<n;++j)
	 b+=(x[i]-xx)*(y[i+1]-yy)-(x[i+1]-xx)*(y[i]-yy);
	 b+=(x[n]-xx)*(y[1]-yy)-(x[1]-xx)*(y[n]-yy);
         if(b==a1) np++;
	 }
 fprintf(g,"%d\n",np);
 fclose(f);
 fclose(g);
 return 0;
}