You want to build a house on an empty land which reaches all buildings in the shortest amount of distance. You can only move up, down, left and right. You are given a 2D grid of values 0, 1 or 2, where:
- Each 0 marks an empty land which you can pass by freely.
- Each 1 marks a building which you cannot pass through.
- Each 2 marks an obstacle which you cannot pass through.
Example:
Input: [[1,0,2,0,1],[0,0,0,0,0],[0,0,1,0,0]] 1 - 0 - 2 - 0 - 1 | | | | | 0 - 0 - 0 - 0 - 0 | | | | | 0 - 0 - 1 - 0 - 0 Output: 7 Explanation: Given three buildings at(0,0),(0,4),(2,2), and an obstacle at(0,2), the point(1,2)is an ideal empty land to build a house, as the total travel distance of 3+3+1=7 is minimal. So return 7.
Note:
There will be at least one building. If it is not possible to build such house according to the above rules, return -1.
[Breadth-First Search] [Array] [Matrix]
- Walls and Gates (Medium)
- Best Meeting Point (Hard)
- As Far from Land as Possible (Medium)