Cod sursa(job #372455)
Utilizator | Data | 10 decembrie 2009 12:00:34 | |
---|---|---|---|
Problema | Ciurul lui Eratosthenes | Scor | 0 |
Compilator | cpp | Status | done |
Runda | Arhiva educationala | Marime | 0.28 kb |
#include <iostream>
#include <fstream>
using namespace std;
ifstream I("ciur.in");
ofstream O("ciur.out");
bool prim[2000000];
p,n,c;
int main () {
I>>n;
for (int i = 2;i <= n;i ++) {
if (!prim[i]) {
c++;
for (int j = 2*i;j <= n; j = j+i)
prim[j]=1;
}
}
O<<c;
}