Cod sursa(job #3360968)

Utilizator nistor_dora_valentinaNistor Dora Valentina nistor_dora_valentina Data 17 iulie 2026 19:09:10
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.35 kb
#include <fstream>

using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int n, i, j, nr;
bool ciur[2000005];
int main()
{
    fin>>n;
    ciur[0]=ciur[1]=1;
    for(i=2; i<=n; i++)
        if(ciur[i]==0)
    {
        nr++;
        for(j=2*i; j<=n; j+=i)
            ciur[j]=1;
    }
    fout<<nr;
    return 0;
}