Leetcode: Remove Element

http://oj.leetcode.com/problems/remove-element/

class Solution {public:    int removeElement(int A[], int n, int elem) {        if(n==0) return 0;        int start=0, end=n-1;        while(start<end){            while(start<end&&A[start]!=elem) start++;            while(start<end&&A[end]==elem) end--;            swap(A[start],A[end]);        }        if(A[start]==elem) return start;        else return start+1;    }};