Cod sursa(job #1596962)
| Utilizator | Data | 11 februarie 2016 15:45:50 | |
|---|---|---|---|
| Problema | Ciurul lui Eratosthenes | Scor | 30 |
| Compilator | cpp | Status | done |
| Runda | Arhiva educationala | Marime | 0.69 kb |
#include <iostream>
#include <fstream>
#include <bitset>
#include <stdio.h>
#include <cmath>
#define MAX 2000003
#define MAX2 46340
using namespace std;
ifstream in("ciur.in");
ofstream out("ciur.out");
bitset<MAX> v;
int n,k;
int main() {
in >> n;
int sq = sqrt(0xffffffff/2);
cout << sq;
for(int i = 2; i <= n; i++) {
if(v[i] == 0) {
if(i > MAX2)
continue;
k++;
int mult = i*i;
//cout << mult << '\n';
while(mult <= n) {
v[mult] = 1;
mult += i;
}
}
}
out << k;
return 0;
}
