Cod sursa(job #788319)
Utilizator | Data | 14 septembrie 2012 14:47:35 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.3 kb |
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int v[2000000],n,i,j,nr;
int main ()
{
f>>n;
nr=0;
for(i=2;i<=n;i++)
{
if(v[i]==0)
{
for(j=2*i;j<=n;j=j+i)
v[j]=1;
nr++;
}
}
g<<nr;
f.close();g.close();
return 0;
}