LeetCode 27.Remove Element

题目描述

• Given an array and a value, remove all instances of that value in-place and return the new length. 
  Do not allocate extra space for another array, you must do this by modifying the input array in-place with O(1) extra memory. 
  The order of elements can be changed. It doesn’t matter what you leave beyond the new length.

• Examlple :

Given nums = [3,2,2,3], val = 3, 
Your function should return length = 2, with the first two elements of nums being 2.

代码实现  

class Solution{
	public: 
		int removeElement(vector<int>& nums, int val){
			int n = nums.size();
			int i, j;
			i = j = 0;
			while(i < n){
				if(nums[i] == val){
					i++;
				} else {
					nums[j++] = nums[i++];			
			    }		
			}
		    return j;
		}
	};