题目 Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…

题目: Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded…

题目: 岛屿的个数 给一个01矩阵,求不同的岛屿的个数. 0代表海,1代表岛,如果两个1相邻,那么这两个1属于同一个岛.我们只考虑上下左右为相邻. 样例 在矩阵: [ [1, 1, 0, 0, 0], [0, 1, 0, 0, 1], [0, 0, 0, 1, 1], [0, 0, 0, 0, 0], [0, 0, 0, 0, 1] ] 中有 3 个岛. 解题: 在programcreek看到是根据深度优先算法 对某个位置(i,j) 当是1 的时候,是岛屿,该位置设为 0 ,并将四周的 1 设置…

给定 '1'(陆地)和 '0'(水)的二维网格图,计算岛屿的数量.一个岛被水包围,并且通过水平或垂直连接相邻的陆地而形成.你可以假设网格的四个边均被水包围.示例 1:11110110101100000000答案: 1示例 2:11000110000010000011答案: 3 详见:https://leetcode.com/problems/number-of-islands/description/ Java实现: class Solution { public int numIslands(…

给定一个由 '1'(陆地)和 '0'(水)组成的的二维网格,计算岛屿的数量.一个岛被水包围,并且它是通过水平方向或垂直方向上相邻的陆地连接而成的.你可以假设网格的四个边均被水包围. 示例 1: 输入: 11110 11010 11000 00000 输出: 1 示例 2: 输入: 11000 11000 00100 00011 输出: 3 广度优先搜索 class Solution { public: int dx[4] = {1, -1, 0, 0}; int dy[4] = {0, 0, 1…

dfs的第一题 被边界和0包围的1才是岛屿,问题就是分理出连续的1 思路是遍历数组数岛屿,dfs四个方向,遇到1后把周围连续的1置零,代表一个岛屿. /* 思路是:遍历二维数组,遇到1就把周围连续的1变成0,res+1,然后继续遍历,直到结束 周围连续1置零用的是dfs,向四个位置搜索,遇到0返回 */ public int numIslands(char[][] grid) { if (grid.length==0) return 0; int r = grid.length; int c =…

A 2d grid map of m rows and n columns is initially filled with water. We may perform an addLand operation which turns the water at position (row, col) into a land. Given a list of positions to operate, count the number of islands after each addLand o…

Given a 2d grid map of '1's (land) and '0's (water), count the number of islands. An island is surrounded by water and is formed by connecting adjacent lands horizontally or vertically. You may assume all four edges of the grid are all surrounded by…