Submission

Score: 100

User: navysrimuang

Problemset: จำนวนเฉพาะก่อนหน้า

Language: cpp

Time: 0.048 second

Submitted On: 2025-10-06 14:01:25

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

int main(){
  
    //sieve
    long long n;cin >> n;
    vector<bool>prime(n+1,0);
    prime[0] = 1;
    prime[1] = 1;
    for(long long i = 2;i<=n;i++){
        if(prime[i] == 0){
            for(long long j = 2*i;j<=n;j+=i ){
                prime[j] = 1;
            }
        }
    }
    

    //travel back;
    int cnt = 0;
    int ans[5];
    while(cnt!=5){
        n--;
        if(prime[n] == 0){
            ans[cnt] = n;
            cnt++;
        }
    }
    
    
    
    
    //just printing nigga
    while(cnt--){
        cout << ans[cnt] << " ";
    }
 
    
    return 0;
}