Cod sursa(job #1081998)

Utilizator luizaelenaLuiza Cucu luizaelena Data 14 ianuarie 2014 00:34:41
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
#include <fstream>
#include<math.h>
 
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{
   bool v[2000001]={0};
    int n,i,p,aux=0;
 
    f>>n;
    for(i=2;i<=sqrt(n);i++)
        if(v[i]==0)
        for(p=i+i;p<=n;p=p+i)
        v[p]=1;
 
for(i=2;i<=n;i++)
 
if(v[i]==0)
   aux++;
g<<aux;
 
    return 0;
}