Cod sursa(job #377043)
Utilizator | Data | 23 decembrie 2009 10:41:26 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.34 kb |
#include<stdio.h>
using namespace std;
long N,j,nr,i;
char v[2000005];
int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%ld", &N);
for(i=2;i<=N;i++)
if(v[i]==0)
{
nr++;
for(j=i+i;j<=N;j=j+i)
if(v[j]==0)
v[j]=1;
}
printf("%ld",nr);
return 0;
}