Cod sursa(job #523605)
Utilizator | Data | 18 ianuarie 2011 17:20:09 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 100 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.27 kb |
#include<stdio.h>
int n,nr,i,j;
bool a[2000001];
int main()
{
freopen("ciur.in","rt",stdin);
freopen("ciur.out","wt",stdout);
scanf("%d",&n);
for(i=2;i<=n;i++)
if(!a[i])
{
nr++;
for(j=i+i;j<=n;j+=i) a[j]=1;
}
printf("%d",nr);
return 0;
}