Facebook Intern Interview question : Remove Elements

This is a facebook intern interview question.

Problem:
Given an array and a value, remove all instances of that value in place and return the new length.

Solution:


class Solution {
public:
    int removeElement(int array[], int len, int elem) {
        // Start typing your C/C++ solution below
        // DO NOT write int main() function
        int start = 0, end = len - 1;
        if (len == 0)
            return 0;

        while (start <= end) {
            if (array[start] == elem) {
                swap(array[start], array[end]);
                end--;
            } else {
                start++;
            }
        }
        return start;
    }

    void swap(int &first, int &second) {
        int temp;
        temp = first;
        first = second;
        second = temp;
    }
};