Cod sursa(job #184847)
Utilizator | Data | 24 aprilie 2008 13:20:10 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include<stdio.h>
long n,k;
long a[2000005];
int main()
{
long i,j;
freopen("ciur.in","r",stdin);
freopen("ciur.out","w",stdout);
scanf("%ld",&n);
/*a=new char[n+2];*/
for(i=2;i<=n;++i)
a[i]=1;
for(i=1;i<=n;++i)
if(a[i]==1){
k++;
for(j=i+i;j<=n;j+=i)
a[j]=0;
}
printf("%ld\n",k);
return 0;
}