Cod sursa(job #749347)

Utilizator mariamFiciu Maria mariam Data 16 mai 2012 18:39:48
Problema Ciurul lui Eratosthenes Scor 40
Compilator cpp Status done
Runda Arhiva educationala Marime 0.32 kb
Raporteaza aceasta sursa 
#include<fstream>
using namespace std;
char a[1000000];
int i,j,x,np;
int main()
{
	ifstream f("ciur.in");
	ofstream g("ciur.out");
	f>>x;
	for(i=2;i<=x;i++)
		a[i]=1;
	for(i=2;i<=x;i++)
		if(a[i]==1)
			for(j=i+i;j<=x;j=j+i)
				a[j]=0;
	for(i=2;i<=x;i++)
		if(a[i]==1) np++;
	g<<np;
		
		
	return 0;
}