Cod sursa(job #1119152)

Utilizator 4afterfunDocTordoi 4afterfun Data 24 februarie 2014 15:41:56
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <iostream>
#include <cstdio>
#include <bitset>

using namespace std;
long long n,z;
bitset <3000000> a;

int main()
{
    cin >> n;
    z++;
    for(long long i=3; i<=n; i+=2){
        if(a[i] == 0)
            z++;
        for(long long j=i*i; j<=n; j+=2*i)
            a[j] = 1;
    }
    cout << z << endl;
}