Snakes and Ladders BFS | Dataford Interview Questions

Snakes and Ladders (LeetCode 909, BFS).

Asked in the DSA stage. Implement the shortest path in a Snakes and Ladders board where each move is a dice roll from 1 to 6. Given an n x n board, return the minimum number of moves needed to reach square n*n, or -1 if it is unreachable.

Function

def snakes_and_ladders(board):

Input

board: a 2D list of integers, where -1 means a normal square and any positive value is the destination square of a snake or ladder.

Output

Return an integer, the minimum number of dice rolls to reach the last square.

Constraints

2 <= n <= 20
board.length == board[i].length == n
board[i][j] is -1 or a value in [1, n*n]
Square 1 is always the starting square
Square n*n is the target square

Function Signature

def snakes_and_ladders(board):

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Problem