27. Remove Element

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 in place with constant memory.

The order of elements can be changed. It doesn't matter what you leave beyond the new length.

Example: Given input array nums = [3,2,2,3] and val = 3, your function should return length = 2, with the first two elements of nums being 2.

Approach: It is a very simple approach where we modify the array on the go by adding only those elements that do not match the target value. 

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

Here is the link to the ideone solution : http://ideone.com/SqojbY