Cod sursa(job #1553230)

Utilizator maria15Maria Dinca maria15 Data 19 decembrie 2015 14:10:26
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
#include <fstream>

using namespace std;

int i, n, j;
char v[2000001];
int main () {
    ifstream fin ("ciur.in");
    ofstream fout("ciur.out");
    int p=0;
    fin>>n;
    for(i=2;i<=n;i++)
        if(v[i]==0){
            p++;
            for(j=2*i;j<=n;j+=i)
                v[j]=1;
        }

    fout<<p;
    return 0;
}