矩阵

有效的数独

Check if a 9x9 Sudoku board is valid by scanning rows, columns, and sub-boxes with hash lookups, ensuring no duplicates …

解数独

Solve the Sudoku puzzle by filling empty cells while respecting Sudoku's rules using array scanning and backtracking.

旋转图像

Rotate an n x n matrix 90 degrees clockwise in-place using array manipulation and mathematical indexing techniques effic…

螺旋矩阵

Given an m x n matrix, return all elements in spiral order starting from the top-left corner.

螺旋矩阵 II

Generate a spiral matrix of size n x n, filled with elements from 1 to n² in spiral order, for interview-focused solving…

不同路径 II

Calculate the number of unique paths from top-left to bottom-right in a grid with obstacles using dynamic programming st…

最小路径和

Compute the minimum sum from top-left to bottom-right in a grid using state transition dynamic programming efficiently.

矩阵置零

Modify the matrix in place by setting rows and columns to zero when an element is zero.

搜索二维矩阵

Search a 2D matrix efficiently using binary search over its linearized index, ensuring correctness in row-major sorted a…

单词搜索

Solve Word Search with backtracking by exploring adjacent cells to match a target word in a grid.

最大矩形

Compute the largest rectangle of 1's in a binary matrix using dynamic programming and stack-based state transitions effi…

被围绕的区域

Transform the matrix in-place by marking regions surrounded by 'X' as 'X', while keeping border-adjacent 'O's intact.

地下城游戏

Calculate the minimum initial health the knight needs to survive the dungeon using state transition dynamic programming …

岛屿数量

Count the number of distinct islands in a binary grid using array traversal combined with depth-first search exploration…

单词搜索 II

Solve the Word Search II problem using backtracking with pruning to find all words on a board of characters.

最大正方形

Maximal Square is a matrix-based dynamic programming problem that focuses on finding the largest square filled with 1's.

搜索二维矩阵 II

Efficiently search for a target in a 2D matrix using binary search and matrix properties.

生命游戏

Solve the Game of Life by updating each cell based on its eight neighbors using Array and Matrix simulation patterns eff…

二维区域和检索 - 矩阵不可变

Design a 2D matrix class that efficiently handles sum queries with O(1) time complexity using a prefix sum approach.

矩阵中的最长递增路径

Find the length of the longest increasing path in a matrix with given movement constraints using graph techniques.

矩形区域不超过 K 的最大数值和

Solve the "Max Sum of Rectangle No Larger Than K" problem using binary search over the valid sum space to optimize space…

有序矩阵中第 K 小的元素

Find the kth smallest element in a sorted n x n matrix using efficient binary search or heap strategies for optimized me…

接雨水 II

Solve Trapping Rain Water II using breadth-first search and priority queues for efficient water trapping in a matrix.

太平洋大西洋水流问题

Find all cells on an island where water can flow to both the Pacific and Atlantic oceans using DFS or BFS.