Submission

Score: 100

User: punzacp555

Problemset: จำนวนเฉพาะ (2560)

Language: cpp

Time: 0.004 second

Submitted On: 2026-09-30 13:34:21

#include <bits/stdc++.h>
using namespace std;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    int n;
    cin >> n;

    // SOLUTION 1:
    // 
    // bool vis[n];
    // memset(vis, 0, sizeof(vis));

    // for(int i=2; i<n; i++) {
    //     if(vis[i]) continue;
    //     cout << i << "\n";
    //     for(int j=i*i; j<n; j+=i) vis[j] = 1;
    // }

    // SOLUTION 2:

    for(int i=2; i<n; i++) {
        bool isprime = 1;
        for(int j=2; j<=sqrt(i); j++) {
            if(i%j == 0) {
                isprime = 0;
                break;
            }
        }
        if(!isprime) continue;

        cout << i << "\n";
    }

    return 0;
}