Cod sursa(job #1011064)
Utilizator | Data | 16 octombrie 2013 09:39:57 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 90 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.33 kb |
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
bool v[2000000];
int n,i,j,k;
int main ()
{
f>>n;
for (i=2; i*i<=n;i++)
if (v[i]==0)
for (j=i*i;j<=n;j=j+i)
v[j]=1;
k=0;
for (i=2;i<=n;i++)
if (v[i]==0) k++;
g<<k;
}