Cod sursa(job #440027)

Utilizator SpiderManSimoiu Robert SpiderMan Data 11 aprilie 2010 21:31:41
Problema Ciurul lui Eratosthenes Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include<stdio.h>
long n;
int nr=0;
char prim[1000005];
int main()
{
 int i,j;
 freopen("ciur.in","r",stdin);
 freopen("ciur.out","w",stdout);
 scanf("%d",&n);
 for(i=2;i<=n;i++)
  prim[i]=1;
 for(i=2;i<=n;i++)
  if(prim[i]==1)
  {
   nr++;
   for(j=i+i;j<=n;j+=i)
    prim[j]=0;
  }
 printf("%d\n",nr);
 return 0;
}