Cod sursa(job #2290650)

Utilizator sabinpocrisSabin P sabinpocris Data 26 noiembrie 2018 19:56:34
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.28 kb
Raporteaza aceasta sursa 
#include <bits/stdc++.h>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");

bitset<2000010> c;
int n;
int main()
{
    f>>n;
    for(int i=2;i*i<=n;i++)
        if(!c[i])
            for(int j=i*i;j<=n;j+=i)
                c[j]=1;
    g<<n-c.count()-1;
    return 0;
}