Package g1001_1100.s1020_number_of_enclaves

Class Solution

java.lang.Object
g1001_1100.s1020_number_of_enclaves.Solution
public class Solution extends Object
1020 - Number of Enclaves.<p>Medium</p> <p>You are given an <code>m x n</code> binary matrix <code>grid</code>, where <code>0</code> represents a sea cell and <code>1</code> represents a land cell.</p> <p>A <strong>move</strong> consists of walking from one land cell to another adjacent ( <strong>4-directionally</strong> ) land cell or walking off the boundary of the <code>grid</code>.</p> <p>Return <em>the number of land cells in</em> <code>grid</code> <em>for which we cannot walk off the boundary of the grid in any number of <strong>moves</strong></em>.</p> <p><strong>Example 1:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/02/18/enclaves1.jpg" alt="" /></p> <p><strong>Input:</strong> grid = [[0,0,0,0],[1,0,1,0],[0,1,1,0],[0,0,0,0]]</p> <p><strong>Output:</strong> 3</p> <p><strong>Explanation:</strong> There are three 1s that are enclosed by 0s, and one 1 that is not enclosed because its on the boundary.</p> <p><strong>Example 2:</strong></p> <p><img src="https://assets.leetcode.com/uploads/2021/02/18/enclaves2.jpg" alt="" /></p> <p><strong>Input:</strong> grid = [[0,1,1,0],[0,0,1,0],[0,0,1,0],[0,0,0,0]]</p> <p><strong>Output:</strong> 0</p> <p><strong>Explanation:</strong> All 1s are either on the boundary or can reach the boundary.</p> <p><strong>Constraints:</strong></p> <ul> <li><code>m == grid.length</code></li> <li><code>n == grid[i].length</code></li> <li><code>1 <= m, n <= 500</code></li> <li><code>grid[i][j]</code> is either <code>0</code> or <code>1</code>.</li> </ul>

  • Constructor Details

    • Solution

      public Solution()

  • Method Details

    • numEnclaves

      public int numEnclaves(int[][] a)