Leetcode 179.最大数

最大数

给定一组非负整数，重新排列它们的顺序使之组成一个最大的整数。

示例 1:

输入: [10,2]

输出: 210

示例 2:

输入: [3,30,34,5,9]

输出: 9534330

 import java.util.Arrays;
 import java.util.Comparator;

 class Solution {
     public String largestNumber(int[] num) {
         if(null==num||num.length<1)
             return "";
         String[] snum = new String[num.length];
         for(int i=0; i<num.length; i++)
             snum[i] = String.valueOf(num[i]);
         Comparator<String> cmp = new Comparator<String>(){
             @Override
             public int compare(String s1,String s2){
                 String c1 = s1+s2;
                 String c2 = s2+s1;
                 return c2.compareTo(c1);
             }
         };
         Arrays.sort(snum,cmp);
         if(snum[0].charAt(0)=='0')
             return "0";
         StringBuilder ans = new StringBuilder();
         for(String each:snum)
             ans.append(each);
         return ans.toString();
     }
 }