Cod sursa(job #539304)

Utilizator cozminasandica cosmina cozmina Data 22 februarie 2011 20:32:24
Problema Ciurul lui Eratosthenes Scor 20
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include<fstream.h>
ifstream fin("ciur.in");
ofstream fout("ciur.out");
int main()
{
	int n,i,j,nr;
	fin>>n;
	unsigned char a[2000000];
	memset(a,1,sizeof(a));
	a[1]=0;
	nr=0;
	for(i=2;i<=n-1;i++)
		for(j=i+1;j<=n;j++)
			if(j%i==0)
				if(a[i])a[j]=0;
				
		for(i=2;i<=n;i++)
			if(a[i])nr++;
				fout<<nr<<" ";
			return 0;
}