Given a linked list of size N and a key, your task is to complete the function insertInMiddle(), that should insert the key in the middle of the linked list.
The function takes two argument as input, the reference pointer to the head of the linked list and an integer value key, the data to be inserted in the linked list.
There will be T, test cases and for each test case the function will be called separately.
For each test case the function should return the reference pointer to the head of the linked list.
1 2 4
10 20 40 50
1 2 3 4
10 20 30 40 50
Note:The Input/Ouput format and Example given are used for system's internal purpose, and should be used by a user for Expected Output only. As it is a function problem, hence a user should not read any input from stdin/console. The task is to complete the function specified, and not to write the full code.