Cod sursa(job #1452665)
Utilizator | Data | 21 iunie 2015 16:33:31 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 20 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.32 kb |
#include<fstream>
using namespace std;
ifstream f("ciur.in");
ofstream g("ciur.out");
int n,i,j,v[2000001],k;
int main()
{
f>>n;
for(i=1;i<=n;++i) v[i]=1;
for(i=2;i<=n;++i)
for(j=2;j<=n;++j) v[i*j]=0;
for(i=2;i<=n;++i) if(v[i]==1) k++;
g<<k;
g.close();
return 0;
}