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Added task 695.

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	`1`	`+package g0601_0700.s0695_max_area_of_island;`
	`2`	`+`
	`3`	`+// #Medium #Array #Depth_First_Search #Breadth_First_Search #Matrix #Union_Find`
	`4`	`+`
	`5`	`+public class Solution {`
	`6`	`+ public int maxAreaOfIsland(int[][] grid) {`
	`7`	`+ if (grid == null \|\| grid.length == 0) {`
	`8`	`+ return 0;`
	`9`	`+ }`
	`10`	`+ int m = grid.length;`
	`11`	`+ int n = grid[0].length;`
	`12`	`+ int max = 0;`
	`13`	`+ for (int i = 0; i < m; i++) {`
	`14`	`+ for (int j = 0; j < n; j++) {`
	`15`	`+ if (grid[i][j] == 1) {`
	`16`	`+ int area = dfs(grid, i, j, m, n, 0);`
	`17`	`+ max = Math.max(area, max);`
	`18`	`+ }`
	`19`	`+ }`
	`20`	`+ }`
	`21`	`+ return max;`
	`22`	`+ }`
	`23`	`+`
	`24`	`+ private int dfs(int[][] grid, int i, int j, int m, int n, int area) {`
	`25`	`+ if (i < 0 \|\| i >= m \|\| j < 0 \|\| j >= n \|\| grid[i][j] == 0) {`
	`26`	`+ return area;`
	`27`	`+ }`
	`28`	`+ grid[i][j] = 0;`
	`29`	`+ area++;`
	`30`	`+ area = dfs(grid, i + 1, j, m, n, area);`
	`31`	`+ area = dfs(grid, i, j + 1, m, n, area);`
	`32`	`+ area = dfs(grid, i - 1, j, m, n, area);`
	`33`	`+ area = dfs(grid, i, j - 1, m, n, area);`
	`34`	`+ return area;`
	`35`	`+ }`
	`36`	`+}`

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	`1`	`+695\. Max Area of Island`
	`2`	`+`
	`3`	`+Medium`
	`4`	`+`
	`5`	+You are given an `m x n` binary matrix `grid`. An island is a group of `1`'s (representing land) connected 4-directionally (horizontal or vertical.) You may assume all four edges of the grid are surrounded by water.
	`6`	`+`
	`7`	+The area of an island is the number of cells with a value `1` in the island.
	`8`	`+`
	`9`	+Return _the maximum area of an island in_ `grid`. If there is no island, return `0`.
	`10`	`+`
	`11`	`+Example 1:`
	`12`	`+`
	`13`	`+![](https://assets.leetcode.com/uploads/2021/05/01/maxarea1-grid.jpg)`
	`14`	`+`
	`15`	`+Input: grid = [[0,0,1,0,0,0,0,1,0,0,0,0,0],[0,0,0,0,0,0,0,1,1,1,0,0,0],[0,1,1,0,1,0,0,0,0,0,0,0,0],[0,1,0,0,1,1,0,0,1,0,1,0,0],[0,1,0,0,1,1,0,0,1,1,1,0,0],[0,0,0,0,0,0,0,0,0,0,1,0,0],[0,0,0,0,0,0,0,1,1,1,0,0,0],[0,0,0,0,0,0,0,1,1,0,0,0,0]]`
	`16`	`+`
	`17`	`+Output: 6`
	`18`	`+`
	`19`	`+Explanation: The answer is not 11, because the island must be connected 4-directionally.`
	`20`	`+`
	`21`	`+Example 2:`
	`22`	`+`
	`23`	`+Input: grid = [[0,0,0,0,0,0,0,0]]`
	`24`	`+`
	`25`	`+Output: 0`
	`26`	`+`
	`27`	`+Constraints:`
	`28`	`+`
	`29`	+* `m == grid.length`
	`30`	+* `n == grid[i].length`
	`31`	+* `1 <= m, n <= 50`
	`32`	+* `grid[i][j]` is either `0` or `1`.

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	`1`	`+package g0601_0700.s0695_max_area_of_island;`
	`2`	`+`
	`3`	`+import static org.hamcrest.CoreMatchers.equalTo;`
	`4`	`+import static org.hamcrest.MatcherAssert.assertThat;`
	`5`	`+`
	`6`	`+import org.junit.jupiter.api.Test;`
	`7`	`+`
	`8`	`+class SolutionTest {`
	`9`	`+ @Test`
	`10`	`+ void maxAreaOfIsland() {`
	`11`	`+ int[][] grid = {`
	`12`	`+ {0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0},`
	`13`	`+ {0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0},`
	`14`	`+ {0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0},`
	`15`	`+ {0, 1, 0, 0, 1, 1, 0, 0, 1, 0, 1, 0, 0},`
	`16`	`+ {0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0},`
	`17`	`+ {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0},`
	`18`	`+ {0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0},`
	`19`	`+ {0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0}`
	`20`	`+ };`
	`21`	`+ assertThat(new Solution().maxAreaOfIsland(grid), equalTo(6));`
	`22`	`+ }`
	`23`	`+`
	`24`	`+ @Test`
	`25`	`+ void maxAreaOfIsland2() {`
	`26`	`+ int[][] grid = {{0, 0, 0, 0, 0, 0, 0, 0}};`
	`27`	`+ assertThat(new Solution().maxAreaOfIsland(grid), equalTo(0));`
	`28`	`+ }`
	`29`	`+}`

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