Cod sursa(job #248637)

Utilizator danypdDani Daniel danypd Data 26 ianuarie 2009 12:54:56
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.27 kb
Raporteaza aceasta sursa 
#include<fstream.h>
ifstream f("ciur.in");
ofstream g("ciur.out");
int main()
{unsigned long N,i,j,a[20000],x=0;
f>>N;
for(i=1;i<=N;i++)
    a[i]=1;
for(i=2;i<=N;i++)
	if(a[i]==1)
		x++;
     for(j=i+i;j<=N;j=j+i)
		 a[j]=0;
	 
g<<x;
f.close();g.close();
return 0;}