- Difficulty: Medium
- Tags: LeetCode, Medium, Depth-First Search, Breadth-First Search, Array, Matrix, leetcode-490, O(max(r, c) * w), O(w)
Problem
There is a ball in a maze
with empty spaces (represented as 0
) and walls (represented as 1
). The ball can go through the empty spaces by rolling up, down, left or right, but it won't stop rolling until hitting a wall. When the ball stops, it could choose the next direction.
Given the m x n
maze
, the ball's start
position and the destination
, where start = [startrow, startcol]
and destination = [destinationrow, destinationcol]
, return true
if the ball can stop at the destination, otherwise return false
.
You may assume that the borders of the maze are all walls (see examples).
Example 1:
Input: maze = [[0,0,1,0,0],[0,0,0,0,0],[0,0,0,1,0],[1,1,0,1,1],[0,0,0,0,0]], start = [0,4], destination = [4,4] Output: true Explanation: One possible way is : left -> down -> left -> down -> right -> down -> right.
Example 2:
Input: maze = [[0,0,1,0,0],[0,0,0,0,0],[0,0,0,1,0],[1,1,0,1,1],[0,0,0,0,0]], start = [0,4], destination = [3,2] Output: false Explanation: There is no way for the ball to stop at the destination. Notice that you can pass through the destination but you cannot stop there.
Example 3:
Input: maze = [[0,0,0,0,0],[1,1,0,0,1],[0,0,0,0,0],[0,1,0,0,1],[0,1,0,0,0]], start = [4,3], destination = [0,1] Output: false
Constraints:
m == maze.length
n == maze[i].length
1 <= m, n <= 100
maze[i][j]
is0
or1
.start.length == 2
destination.length == 2
0 <= startrow, destinationrow <= m
0 <= startcol, destinationcol <= n
- Both the ball and the destination exist in an empty space, and they will not be in the same position initially.
- The maze contains at least 2 empty spaces.