Given a list of N words. Count the number of words that appear exactly twice in the list.

Example 1:

Input: N = 3 list = {Geeks, For, Geeks} Output: 1 Explanation: 'Geeks' is the only word that appears twice. Example 2:

Input: N = 8 list = {Tom, Jerry, Thomas, Tom, Jerry, Courage, Tom, Courage} Output: 2 Explanation: 'Jerry' and 'Courage' are the only words that appears twice.

Your Task:
You dont need to read input or print anything. Complete the function countWords() which takes integer N and list of strings as input parameters and returns the number of words that appear twice in the list.

Expected Time Complexity: O(N) Expected Auxiliary Space: O(N)