Cod sursa(job #163714)
Utilizator | Data | 22 martie 2008 17:25:40 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.3 kb |
#include<fstream>
using namespace std;
char x[64000];
int main()
{long n,i,nr=0,j;
ifstream fin("ciur.in");
ofstream fout("ciur.out");
fin>>n;
for(i=2;i<=n;i++)
if(x[i]==0)
{nr++;
for(j=i;j<=n;j=j+i)
x[j]=1;
}
fout<<nr;
fin.close();
fout.close();
return 0;
}