UVA - 443 - Humble Numbers

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.LinkedList;

public class Main {
   
    public static void main(String[] args) throws IOException {
        InputStreamReader isr = new InputStreamReader(System.in);
        BufferedReader br = new BufferedReader(isr);
        StringBuffer sb = new StringBuffer("");
        String m = "";
        ArrayList<Long> lolz = new ArrayList<Long>();
        int[] p = {2, 3, 5, 7};
        for (int i = 1; i < 11; i++) {
            lolz.add((long) i);
        }
        int index = 0;
        while (lolz.size() < 6843) {
            long temp = lolz.get(index);
            for (int i = 0; i < p.length; i++) {
                if (!lolz.contains(temp * p[i])) {
                    lolz.add(temp * p[i]);
                    long[] arr = new long[lolz.size()];
                    for (int j = 0; j < arr.length; j++) {
                        arr[j] = lolz.get(j);
                    }
                    Arrays.sort(arr);
                    lolz.clear();
                    for (int j = 0; j < arr.length; j++) {
                        lolz.add(arr[j]);
                    }
                }
               
            }
            index++;
        }
        long[] arr = new long[lolz.size()];
                    for (int j = 0; j < arr.length; j++) {
                        arr[j] = lolz.get(j);
                    }
        while (true) {
            int x = Integer.parseInt(br.readLine());
            if (x == 0) {
                break;
            }
            String st=getRank(x);
            sb.append("The ");
            sb.append(x).append(st);
            sb.append(" humble number is ");
            sb.append(arr[x-1]).append(".\n");
        }
        System.out.print(sb);
    }
   
    static String getRank(int x){
        int temp=x%100;
        int z=x%10;
        if(temp>9 && temp<20){
            return "th";
        }else{
            if(z==1)
              return "st";
            else if(z==2)
              return "nd";
            else if(z==3)
               return "rd";
            else
               return "th";              
        }
    }
}