Cod sursa(job #885509)
Utilizator | Data | 22 februarie 2013 08:33:18 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include <fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int v[2000000];
int main()
{
long int n,s=0;
f>>n;
for(int k=2;k<=n;k++)
{
if(!v[k])
{
s++;
for(int i=k*2;i<=n;i=k+i)
v[i]=1;
}
}
g<<s;
}