删除元素（LintCode）

 1 public class Solution {
 2     /** 
 3      *@param A: A list of integers
 4      *@param elem: An integer
 5      *@return: The new length after remove
 6      */
 7     public int removeElement(int[] A, int elem) {
 8         int r = A.length - 1;
 9         if(r < 0) return 0;
10         int i = 0;
11         
12         while(r > i) {
13             if(A[i] == elem) {
14                 while(A[r] == elem && r > 0) r--;
15                 if(r > i) {
16                     A[i] = A[r];
17                     r--;
18                 }
19             }
20             i++;
21         }
22         
23         if(A[r] == elem) r--;
24         
25         return r + 1;
26     }
27 }