Sort the array to the minimum, the equivalent of their own to achieve a String's compareTo function, but alternative.

Title Description

Enter a positive integer array, the array of all the numbers arranged in a number spliced ​​together, the splice can print out all numbers smallest one. 3,32,321 input array} {e.g., print the minimum number of three numbers can be arranged to 321,323.

// one go

Select the sort of thinking, in fact, compare the size of the string, the numbers on the front of the small, but the comparison is the number of bits, for example 3, 23, certainly get 233, we first compare the first character, but if you have the same more trouble, need to be part of that long and the short of the first character comparisons, this is the meaning helper function.

 1 import java.util.ArrayList;
 2 
 3 public class Solution {
 4     public String PrintMinNumber(int [] numbers) {
 5         String res="";
 6         if(numbers.length==0)
 7             return res;
 8         String[] arr=new String[numbers.length];
 9         for(int i=0;i<numbers.length;i++)
10             arr[i]=""+numbers[i];
11         
12         for(int i=0;i<arr.length;i++)
13         {
14             int min=i;
15             for(int j=i;j<arr.length;j++)
16                 if(helper(arr[j],arr[min]))
17                     min=j;
18             swap(arr,i,min);
19         }
20         for(int i=0;i<arr.length;i++)
21             res+=arr[i];
22         return res;
23            
24     }
25     public void swap(String[] arr,int i,int j)
26     {
27         String temp=arr[i];
28         arr[i]=arr[j];
29         arr[j]=temp;
30     }
31     public boolean helper(String s1,String s2)
32     {
33         int len1=s1.length();
34         int len2=s2.length();
35         if(len1>len2)
36         {
37             for(int i=0;i<len1;i++)
38             {
39                 if(i<len2)
40                 {
41                     if(s1.charAt(i)>s2.charAt(i))
42                         return false;
43                     else if(s1.charAt(i)<s2.charAt(i))
44                         return true;
45                 }
46                 else
47                 {
48                     if(s1.charAt(i)<s2.charAt(0))
49                         return true;
50                     else if(s1.charAt(i)>s2.charAt(0))
51                         return false;
52                 }
53             }
54             return true;
55         }
56         else
57         {
58              for(int i=0;i<len2;i++)
59             {
60                 if(i<len1)
61                 {
62                     if(s1.charAt(i)>s2.charAt(i))
63                         return false;
64                     else if(s1.charAt(i)<s2.charAt(i))
65                         return true;
66                 }
67                 else
68                 {
69                     if(s1.charAt(0)<s2.charAt(i))
70                         return true;
71                     else if(s1.charAt(0)>s2.charAt(i))
72                         return false;
73                 }
74             }
75             return true;
76         }
77     }
78    
79 }