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Shortest Path in Binary Matrix (medium)
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Problem Statement

Examples

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Problem Statement

Given a matrix of size m x n, return the length of the shortest path from the top-left corner (0,0) to the bottom-right corner (N-1, N-1). If there is no such path, the output should be -1.

Follow the rules below while calculating the shortest path.

  • You can move horizontally, vertically, and diagonally to adjacent cells.
  • The visited cell should be 0.
  • The path length is counted as the number of steps taken.

Examples

  1. Example 1:
  • Input:
[[0, 0, 0], 
 [0, 1, 0], 
 [0, 0, 0]]
  • Expected Output: 4
  • Justification: The shortest path is (0, 0) -> (1, 0) -> (2, 1) -> (2, 2), totaling 4 steps.
  1. Example 2:
  • Input:
[[0, 1, 0], 
 [0, 0, 0], 
 [0, 1, 0]]
  • Expected Output: 3
  • Justification: The shortest path is (0, 0) -> (1, 1) -> (2, 2), totaling 3 steps.
  1. Example 3:
  • Input:
[1, 1, 1], 
 [0, 1, 1], 
 [0, 0, 0]]
  • Expected Output: -1
  • Justification: The top-left cell can't be visited, as its value is 1. So, it returns -1.

Try it yourself

Try solving this question here:

Python3
Python3

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On this page

Problem Statement

Examples

Try it yourself