Cod sursa(job #160874)
Utilizator | Cotirlea Anamaria Anamaria20 | Data | 17 martie 2008 10:35:25 |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.4 kb |
#include <stdio.h>
FILE* f;
FILE* s;
char sir[200];
int main()
{
f=fopen ("ciur.in","r");
s=fopen ("ciur.out","w");
long int n;
fscanf (f,"%ld",&n);
for (long int i=2;i<=n;i++)
{
for (long int j=i+i;j<=n;j+=i)
{
sir[j]='1';
}
}
long int cnt=0;
for (i=2;i<=n;i++)
{
if (sir[i]!='1')
cnt++;
}
fprintf (s,"%ld",cnt);
fcloseall();
return 0;
}