Cod sursa(job #771374)
Utilizator | Data | 25 iulie 2012 19:28:28 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.25 kb |
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int nr,n,i,v[2000001],j;
int main()
{
f>>n;
for(i=2;i<=n;i++)
if(v[i]==0)
{
nr++;
for(j=i+i;j<=n;j+=i)
v[j]=1;
}
g<<nr;
return 0;
}