Cod sursa(job #630511)
Utilizator | Data | 5 noiembrie 2011 17:49:33 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 10 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include<iostream>
#include<fstream>
using namespace std;
int main ()
{
ifstream f("ciur.in");
ofstream g("ciur.out");
int n,nr=0;
f>>n;
bool x[n+1];
for (int i=2;i<=n;i++)
{
if (x[i]==0)
{
for (int j=i+i;j<=n;j+=i) {
x[j]=1;
}
nr++;
}
}
g<<nr;
f.close(); g.close();
return 0;
}