Cod sursa(job #550555)

Utilizator deadsleeperBanuc Vasilica Angel deadsleeper Data 9 martie 2011 18:58:25
Problema Ciurul lui Eratosthenes Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.33 kb
Raporteaza aceasta sursa 
#include <fstream>
#include <math.h>

using namespace std;
int main()
{

ifstream f("ciur.in");
ofstream g("ciur.out");
       
long int i,j,n,S=0;
f>>n;
char A[n+1];

for (i=1;i<=n;i++) A[i] = 1;

S=1;
for (i=3;i<=n;i+=2)
if (A[i])
{
S++;
for (j=2;j*i<=n;j++) A[j*i] = 0;
}

g<<S;

f.close();
g.close();    
}