Cod sursa(job #2000566)

Utilizator vasilescutiberiu121Vasilescu Costin-Tiberiu vasilescutiberiu121 Data 14 iulie 2017 09:49:46
Problema Ciurul lui Eratosthenes Scor 60
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
#include <iostream>
#include <fstream>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");

bool v[2000000];
int main()
{
    int n, i, m, r=0;
    fin >> n;
    for(i = 2; i<n; i++)for(m = i + i; m<n; m+=i)v[m] = 1;
    for(i = 2; i<n; i++)if(v[i]==0)r++;
    fout << r;
    return 0;
}