Cod sursa(job #1084833)

Utilizator FawkesAndrei Colhon Fawkes Data 16 ianuarie 2014 20:23:50
Problema Ciurul lui Eratosthenes Scor 30
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
#include <iostream>
#include <fstream>

using namespace std;
int a[5000000];
int main()
{
    ifstream f("ciur.in");
    ofstream g("ciur.out");
    int nr=1,n;
    f >> n;
    for(int i=3;i<=n;i=i+2)
    {
        if(a[i]==0)
        ++nr;
        for(int j=i+i;j<=n;j+=i) a[j]=1;
    }
    g << nr;
    return 0;
}