Cod sursa(job #555671)

Utilizator valentin.harsanValentin Harsan valentin.harsan Data 15 martie 2011 18:06:32
Problema Ciurul lui Eratosthenes Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.34 kb
Raporteaza aceasta sursa 
#include<iostream>
#include<fstream>
using namespace std;
int n,u;
void ciur(){
int i,j;
bool c[2000001];
for (i=2;i*i<n;++i) {
if (!c[i]) {
for (j=i*i;j<=n;j+=i)
c[j]=true;
}
}
for (i=2;i<=n;++i) {
if (!c[i]) {
++u;
}
}
ifstream aa("ciur.in");
ofstream ss("ciur.out");
int main() {
aa >> n;
ciur();
ss << u;
return 0;
}