Cod sursa(job #402184)
Utilizator | Data | 23 februarie 2010 16:38:06 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 10 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include<stdio.h>
long i,j,n,qq;
bool c[2000000];
int main()
{
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%ld",&n);
qq=n;
for(i=2;i*i<=n;++i)
if(!c[j])
{
for(j=i*i;j<=n;j+=i)
{
c[j]=true;
qq--;
}
}
printf("%ld",qq-1);
return 0;
}