Cod sursa(job #886569)

Utilizator Impaler_009Mihai Nitu Impaler_009 Data 22 februarie 2013 23:50:01
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.29 kb
#include <fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");

bool v[2000001];
int nr,n,i,x;

int main()
{
    fin>>n;
    for (i=2;i<=n;i++)
    {
        if (v[i]) continue;
        nr++;
        for (x=2*i;x<=n;x=x+i) v[x]=1;
    }
    fout<<nr;
}