Cod sursa(job #3189518)

Utilizator alessandro2Alex Stan alessandro2 Data 5 ianuarie 2024 23:27:42
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <iostream>
#include <fstream>
#include <cmath>
using namespace std;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int j,i,k=0;
bool a[2000001];
int main() {
    int n;
    fin>>n;
    for(i=2;i<=n;i++){
        k=k+1-a[i];
        for(j=i*2;j<=n;j=j+i){
            a[j]=1;
        }
    }
    fout<<k<<endl;
    return 0;
}