2501 약수 구하기(자바)

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.StringTokenizer;


public class Main {
	
	
	public static void main(String[] args) throws IOException {
	
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		StringTokenizer st = new StringTokenizer(br.readLine(), " ");
		int N = Integer.parseInt(st.nextToken());
		int M = Integer.parseInt(st.nextToken());
		
		
		ArrayList<Integer> list = new ArrayList<>();
		
		
		for(int i = 1; i<=N; i++) {
			if(N%i ==0) {
				list.add(i);
			}
		}
		
		if(list.size()<M) {
			System.out.println(0);
		}else {
		System.out.println(list.get(M-1));
	}
}
}