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)
Constraints:
1<= N <= 104