[数据结构与算法]【拼数】【Java】

import java.io.*;
import java.util.*;

public  class Main{
	
	public static void main(String[] args) throws IOException{
		
		StreamTokenizer in = new StreamTokenizer(new BufferedReader(new InputStreamReader(System.in)));
		PrintWriter out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));

		in.nextToken();int N=(int) in.nval;
		
		Integer[]arr=new Integer[N];
		
		for(int i=0;i<N;i++) {
			in.nextToken();arr[i]=(int) in.nval;
		}
		
		Comparator<Integer> comp=new Comparator<Integer>() {

			@Override
			public int compare(Integer o1, Integer o2) {
				int num1=Integer.valueOf(String.valueOf(o1)+String.valueOf(o2));
				int num2=Integer.valueOf(String.valueOf(o2)+String.valueOf(o1));
				if(num1>num2) {
					return -1;
				}else{
					return 1;
				}
			}
		};
		
		Arrays.sort(arr,comp);
		
		String ans="";
		
		for(int a:arr) {
			ans+=String.valueOf(a);
		}
		
		out.print(ans);
		
		
    	out.flush();
    	out.close();
	}
}