Cod sursa(job #2548331)

Utilizator alex_bb8Banilean Alexandru-Ioan alex_bb8 Data 16 februarie 2020 15:31:37
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.36 kb
Raporteaza aceasta sursa 
#include <bits/stdc++.h>

using namespace std;

ifstream f("ciur.in");
ofstream g("ciur.out");


bitset <1000002>p;
int nr,n;

int main()
{

    f>>n;
    for(int i=1;((i*i)<<1)+(i<<1)<=n;++i)
     if(p[i]==0)
     {
        ++nr;
        for(int j=((i*i)<<1)+(i<<1);(j<<1)+1<=n;j+=(i<<1)+1) p[j]=1;

     }

    g<<nr+1;
    return 0;
}