Cod sursa(job #196414)

Utilizator AndreiDDiaconeasa Andrei AndreiD Data 26 iunie 2008 13:15:44
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include <stdio.h>
#define Nmax 2000001

int n,nr=0,i,j;
char p[Nmax];

int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);

scanf("%d",&n);
for (i=2;i<=n;i++)
    p[i]=1;
for (i=2;i<=n;i++)
    if (p[i])
       {
       nr++;
       for (j=i+i;j<=n;j+=i)
	   p[j]=0;
       }
printf("%d",nr);
return 0;
}