Cod sursa(job #251619)

Utilizator mathboyDragos-Alin Rotaru mathboy Data 2 februarie 2009 23:29:53
Problema Ciurul lui Eratosthenes Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
Raporteaza aceasta sursa 
#include <fstream.h>
#define marime 2000001
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{
long unsigned i,n,k,p=0,b;
char a[marime];
f>>n;
for(i=2;i<=n;i++)
	a[i]=i;
for(i=2;i<=n;i++) if(a[i]!=0)
		{ for(k=i+1;k<=n;k++)
		 { if(a[k]%a[i]==0)
			 a[k]=0;
			 } }
 for(i=1;i<=n;i++) {if(a[i]!=0) p++;}
 g<<p;
 return 0;
}