Microsoft algorithm 100 question 68 with the smallest number of arrays

68. Arrange the array to the smallest number.
Title: Enter an array of positive integers, concatenate them into a number, and output the smallest of all the numbers that can be drained.
One.
For example, the input array {32, 321}, the output of these two can be ranked as the smallest number 32132.
Please give an algorithm to solve the problem, and prove that the algorithm

1  PackageCom.rui.microsoft;2 3 Importjava.util.Arrays;4 ImportJava.util.Comparator;5 6  Public classTest68_minimum {7 8      Public Static voidMain (string[] args) {9         int[] A = {3,2,123};TenTest68_minimum app =Newtest68_minimum (); OneString res =App.smallest (a); A System.out.println (res); -     } -      theString Smallest (int[] a) { -integer[] aux =NewInteger[a.length]; -          for(inti = 0; i < a.length; i++){ -Aux[i] =A[i]; +         } -          +Arrays.sort (AUX,NewComparator<integer>() { A  at @Override -              Public intCompare (integer O1, integer o2) { -                 return("" + O1 + O2). CompareTo ("" + O2 +O1); -             } -         }); -          inStringBuilder SB =NewStringBuilder (); -          for(inti = 0; i < aux.length; i++){ to sb.append (Aux[i]); +         } -         returnsb.tostring (); the     } *}

Microsoft algorithm 100 question 68 with the smallest number of arrays