Cod sursa(job #2662132)

Utilizator proflaurianPanaete Adrian proflaurian Data 23 octombrie 2020 16:11:50
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <bits/stdc++.h>

using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
const int N = 2000010;
bitset<N> p;
int n,cnt;
int main()
{
    f>>n;
    for(int i=2;i<=n;i++)
    if(p[i]==0)
    {
        cnt++;
        for(int j=2*i;j<=n;j+=i)
            p[i]=1;
    }
    g<<cnt;
    return 0;
}