Cod sursa(job #1846758)

Utilizator ionutpop712Pop Ionut ionutpop712 Data 14 ianuarie 2017 00:16:11
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include <fstream>

using namespace std;

ifstream in("ciur.in");
ofstream out("ciur.out");
int N, c;
bool v[2000000];

int main()
{
in >> N;
for (int i = 2; i <= N; ++i)
    {
    if (!fr[i])
        {
        ++c;
        for (int j = 2; i*j <= N; ++j)
            fr[j*i]++;
        }
    }
out << c;
    return 0;
}