剑指offer三十二之把数组排成最小的数

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;


public class Solution {
    public String PrintMinNumber(int[] numbers) {
        ArrayList<String> arrayList = new ArrayList<String>();

        //将数组转换成ArrayList<String>
        for (int i = 0; i < numbers.length; i++) {
            arrayList.add(String.valueOf(numbers[i]));
        }

        //排序
        Collections.sort(arrayList, new Comparator<String>() {
            @Override
            public int compare(String o1, String o2) {
                String s1 = o1 + o2;
                String s2 = o2 + o1;
                return s1.compareTo(s2); //按照字典顺序排序
            }
        });

        //合并
        StringBuffer stringBuffer = new StringBuffer();
        for (int i = 0; i < arrayList.size(); i++) {
            stringBuffer.append(arrayList.get(i));
        }

        //返回结果
        return stringBuffer.toString();
    }

}