Cod sursa(job #2339884)

Utilizator Leonard123Mirt Leonard Leonard123 Data 9 februarie 2019 15:03:11
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <fstream>
#include<bitset>
using namespace std;

ifstream cin("ciur.in");
ofstream cout("ciur.out");
bitset <2000005> bit;
int n,cnt=1;
int main()
{
  cin>>n;
  for(int i=3; i<=n; i+=2)
    if(!bit[i]){
        cnt++;
        for(int j=i+i; j<=n; j+=i)
            bit[j]=1;
  }
cout<<cnt;
  return 0;
}