How to Solve Unique Paths I I I Problem
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Unique Paths III
You are given an m x n integer array grid where grid[i][j] could be: 1 representing the starting square. There is exactly one starting square. 2 representing the ending square. There is exactly one en...
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Understanding the Unique Paths I I I Problem
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Problem Statement
You are given an m x n integer array grid where grid[i][j] could be: 1 representing the starting square. There is exactly one starting square. 2 representing the ending square. There is exactly one ending square. 0 representing empty squares we can walk over. -1 representing obstacles that we cannot walk over. Return the number of 4-directional walks from the starting square to the ending square, that walk over every non-obstacle square exactly once.
Unique Paths III
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Examples
grid = [[1,0,0,0],[0,0,0,0],[0,0,2,-1]]2We have the following two paths: 1. (0,0),(0,1),(0,2),(0,3),(1,3),(1,2),(1,1),(1,0),(2,0),(2,1),(2,2) 2. (0,0),(1,0),(2,0),(2,1),(1,1),(0,1),(0,2),(0,3),(1,3),(1,2),(2,2)
grid = [[1,0,0,0],[0,0,0,0],[0,0,0,2]]4We have the following four paths: 1. (0,0),(0,1),(0,2),(0,3),(1,3),(1,2),(1,1),(1,0),(2,0),(2,1),(2,2),(2,3) 2. (0,0),(0,1),(1,1),(1,0),(2,0),(2,1),(2,2),(1,2),(0,2),(0,3),(1,3),(2,3) 3. (0,0),(1,0),(2,0),(2,1),(2,2),(1,2),(1,1),(0,1),(0,2),(0,3),(1,3),(2,3) 4. (0,0),(1,0),(2,0),(2,1),(1,1),(0,1),(0,2),(0,3),(1,3),(1,2),(2,2),(2,3)
grid = [[0,1],[2,0]]0There is no path that walks over every empty square exactly once. Note that the starting and ending square can be anywhere in the grid.
Constraints
m == grid.lengthn == grid[i].length1 <= m, n <= 201 <= m * n <= 201 <= grid[i][j] <= 2There is exactly one starting cell and one ending cell.How Interview Coder Helps with Leetcode Problems
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