Cod sursa(job #159937)

Utilizator Ionutz_LalaLala Marius Ionut Ionutz_Lala Data 14 martie 2008 15:46:48
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
Raporteaza aceasta sursa 
#include <stdio.h>
FILE *f=fopen("ciur.in","r"),*g=fopen("ciur.out","w");
int n,p,i,j;
char prim[2000001];
int main(void)
{
 fscanf(f,"%d",&n);
 for(i=2;i<=n;i++)
   if(!prim[i])
   {
     p++;
     for(j=2*i;j<=n;j+=i)
       prim[j]=1;
   }
 fprintf(g,"%d",p);
 return 0;
}