Cod sursa(job #592036)

Utilizator morlockRadu Tatomir morlock Data 26 mai 2011 14:53:05
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.35 kb
Raporteaza aceasta sursa 
#include <stdio.h>

int n, nr=0, i, j;
char v[2000000];

int main()
{
	freopen("ciur.in", "r", stdin);
	freopen("ciur.out", "w", stdout);
	
	scanf("%d", &n);
	
	for (i=2; i<=n; ++i)
		v[i]=1;
	
	for (i=2; i<=n; ++i)
	{
		if ( v[i] )
		{
			++nr;
			for (j=i+i; j<=n; j += i)
				v[j]=0;
		}
	}
	
	printf("%d\n", nr);
	
	
return 0;	
}