Calculate the Manhattan Distance between two cells of given 2D array

Given a 2D array of size M * N and two points in the form (X₁, Y₁) and (X₂ , Y₂) where X₁ and X₂ represents the rows and Y₁ and Y₂ represents the column. The task is to calculate the Manhattan distance between the given points. 

Examples:

Input: M = 5, N = 5, X₁ = 1, Y₁ = 2, X₂ = 3, Y₂ = 3
Output: 3
Explanation: As per the definition, the Manhattan the distance is same as sum of the absolute difference of the coordinates.

Input: M = 5, N = 5, X₁ = 4, Y₁ = 2, X₂ = 4, Y₂ = 2
Output: 0

Approach: The approach is based on mathematical observation. The Manhattan distance between two points is the sum of absolute difference of the coordinates.

Manhattan distance = |X₁ - X₂| + |Y₁ - Y₂|

Below is the implementation of the above approach.

3

Time Complexity: O(1)
Auxiliary Space: O(1)