题解 | #小红的好数#

#include <iostream>
#include <set>
#include <string>
#include <vector>
using namespace std;
vector<string> ans;
bool check(string &s)
{
	set<char> chk(s.begin(),s.end());
	return chk.size()==s.size();
}
int main(void)
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	string s;
	int i,k;
	for(i=99999;i>=10000;--i)
	{
		s=to_string(i);
		if(check(s))
			ans.emplace_back(s);
	}
	for(i=9999;i>=1000;--i)
	{
		s="0"+to_string(i);
		if(check(s))
			ans.emplace_back(s);
	}
	cin>>k;
	cout<<ans[k-1];
	return 0;
}

import java.util.*;
public class ZT14 {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        ArrayList<String> ans=new ArrayList<>();
        int i,k;
        for(i=99999;i>=10000;--i){
            String s=""+i;
            if(check(s))
                ans.add(s);
        }
        for(i=9999;i>=1000;--i){
            String s="0"+i;
            if(check(s))
                ans.add(s);
        }
        k=sc.nextInt();
        System.out.println(ans.get(k-1));
    }
    public static boolean check(String s){
        Set<Character> chk=new HashSet<>();
        for(int i=0;i<s.length();i++)
            chk.add(s.charAt(i));
        return chk.size()==s.length();
    }
}

ans=[]

def check(s:str)->bool:
    chk=set(s)
    return len(chk)==len(s)

for i in range(99999,9999,-1):
    s=str(i)
    if(check(s)):
        ans.append(s)
for i in range(9999,999,-1):
    s='0'+str(i)
    if(check(s)):
        ans.append(s)

k=int(input())
print(ans[k-1])