Submission

Score: 100

User: rice_ot

Problemset: จำนวนเฉพาะก่อนหน้า

Language: cpp

Time: 0.030 second

Submitted On: 2025-10-14 15:22:09

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

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