Cod sursa(job #208486)
Utilizator | Data | 16 septembrie 2008 19:22:01 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.35 kb |
#include <fstream.h>
ifstream fin("ciur.in");
ofstream fout("ciur.out");
unsigned char a[32000];
int main()
{
unsigned long n, i, c, j;
fin >> n;
for( i = 2; i <= n; i++ )
{
if(!a[i])
{
c++;
for( j = i+i; j <=n; j += i )
a[j] = 1;
}
}
fout << c;
fout.close();
return 0;
}