Cod sursa(job #296719)
Utilizator | Data | 5 aprilie 2009 01:36:14 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include <stdio.h>
int n,nr;
char ok[2000009];
int main()
{
int n,i,j,nr;
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%d",&n);
for (i=2;i<=n;i++) ok[i]=0;nr=0;
for (i=2;i<=n;i++)
if (ok[i]=0) {nr++; for (j=i+i;j<= n; j+=i) ok[j] = 1; }
printf("%d",nr);
return 0;}