2684. Maximum Number of Moves in a Grid ## 思路 解法1. 直接照題目做DFS 解法2. 因為每次move都是往c+1移動 直接for loop檢查並記錄下一步可以到的row set 如果沒有就回傳目前的col index ## Code DFS ```python class Solution: def maxMoves(self, grid: List[List[int]]) -> int: len_r, len_c = len(grid), len(grid[0]) @cache def recur(r, c): max_moves = 0 for nr, nc in (r-1, c+1), (r, c+1), (r+1, c+1): if 0 <= nr < len_r and 0 <= nc < len_c and grid[r][c] < grid[nr][nc]: max_moves = max(max_moves, 1 + recur(nr, nc)) return max_moves res = 0 for r in range(len_r): res = max(res, recur(r, 0)) return res ``` ```python class Solution: def maxMoves(self, grid: List[List[int]]) -> int: len_r, len_c = len(grid), len(grid[0]) curr_r = {r for r in range(len_r)} for c in range(len_c-1): next_r = set() for r in curr_r: for nr in (r-1, r, r+1): if 0 <= nr < len_r and grid[nr][c+1] > grid[r][c]: next_r.add(nr) if not next_r: return c curr_r = next_r return len_c-1 ``` -- https://i.imgur.com/kyBhy6o.jpeg -- ※ 發信站: 批踢踢實業坊(ptt-club.com.tw), 來自: 185.213.82.25 (臺灣) ※ 文章網址: https://ptt-club.com.tw/Marginalman/M.1730201059.A.82F