Cod sursa(job #296700)
Utilizator | Data | 5 aprilie 2009 00:36:22 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include <stdio.h>
int main()
{ char ok[2000000];
long int n,i,j,nr;
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%ld",&n);
for (i=2;i<=n;i++) ok[i]=0;nr=0;
for (i=2;i<=n;i++)
if (!ok[i]) {nr++; for (j=1;j<=n/2;j++) ok[i*j]=1;}
printf("%ld",nr);
return 0;}