Submission

Score: 100

User: Bestzu

Problemset: จำนวนเฉพาะก่อนหน้า

Language: cpp

Time: 0.030 second

Submitted On: 2025-10-15 12:05:50

#include <bits/stdc++.h>
#define endl '\n'
#define ll long long int
using namespace std;



int main() {
    ios::sync_with_stdio(false); cin.tie(0);

    int n; cin >> n;
    vector<bool> isPrime(n, true);
    isPrime[0] = isPrime[1] = false;
    
    for(int i = 2; i*i <= n; i++) {
    	if(isPrime[i]) {
    		for(int j = i*i; j <= n; j += i) {
    			isPrime[j] = false;
			}
		}
	}
	
	int cnt = 0;
	vector<int> ans;
	for(int i = n-1; i >= 2; i--) {
		if(cnt == 5) break;
		if(isPrime[i]) {
			ans.push_back(i);
			cnt++;
		}
	}
	sort(ans.begin(), ans.end());
	for(auto &e : ans) cout << e << " ";
    return 0;
}