296. Best Meeting Point

A group of two or more people wants to meet and minimize the total travel distance. You are given a 2D grid of values 0 or 1, where each 1 marks the home of someone in the group. The distance is calculated using Manhattan Distance , where distance(p1, p2) = |p2.x - p1.x| + |p2.y - p1.y| .

Example:

Input:

 
1 - 0 - 0 - 0 - 1
|   |   |   |   |
0 - 0 - 0 - 0 - 0
|   |   |   |   |
0 - 0 - 1 - 0 - 0
Output: 6 
Explanation: 

Given three people living at 
(0,0)

, 
(0,4)

, and 
(2,2)

:
             The point 
(0,2)

 is an ideal meeting point, as the total travel distance 
             of 2+2+2=6 is minimal. So return 6.