Submission

Score: 100

User: nattawin

Problemset: จำนวนเฉพาะก่อนหน้า

Language: cpp

Time: 0.030 second

Submitted On: 2026-10-06 15:49:50

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

int main()
{
	int n,jo = 0;
	set<int> arr={};
	cin>>n;
    vector<bool> prime(n + 1, true);
    for (int p = 2; p * p <= n; p++) {
        if (prime[p] == true) {
            
            // marking as false
            for (int i = p * p; i <= n; i += p)
                prime[i] = false;
        }
	}
	for(int i = n-1 ; i > 2 ; i--)
	{
		if(prime[i]==true)
		{
//			cout<<i<<" ";
			arr.insert(i);
			jo+=1;
		}
		if(jo==5)
		{
			for(int x : arr)
			{
				cout<<x<<" ";
			
			}
			return 0;			
		}
	}
	
}