Cod sursa(job #700431)
Utilizator | Data | 1 martie 2012 10:19:21 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.31 kb |
#include<iostream.h>
#include<fstream.h>
bool c[2000001];
int main()
{
fstream fin("ciur.in",ios::in);
fstream fout("ciur.out",ios::out);
short int n,s=0;
fin>>n;
for (short int i=2;i<=n;i++)
if(! c[i])
{
s++;
for(short int j=i;j<=n;j+=i)
c[j]=1;
}
fout<<s;
return 0;
}