Cod sursa(job #291684)
Utilizator | Data | 30 martie 2009 10:18:16 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 30 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.45 kb |
#include <fstream.h>
#include<math.h>
int N, cnt;
int prim(int X)
{
int i;
for (i = 2; i<=sqrt(X); i++)
if (X % i == 0)
return 0;
return 1;
}
int main(void)
{
int i;
ifstream f("ciur.in");
ofstream g("ciur.out");
f>>N;
for (i = 2; i <= N; i++)
if (prim(i))
cnt++;
g<<cnt<<"\n";
return 0;
}