Update 0102.沉没孤岛.md

Update 0102.沉没孤岛.md

problems/kamacoder/0102.沉没孤岛.md

@@ -138,8 +138,128 @@ int main() {
 
 ### Java 
 
+```JAVA
+
+import java.util.Scanner;
+
+public class Main {
+    static int[][] dir = { {-1, 0}, {0, -1}, {1, 0}, {0, 1} }; // 保存四个方向
+
+    public static void dfs(int[][] grid, int x, int y) {
+        grid[x][y] = 2;
+        for (int[] d : dir) {
+            int nextX = x + d[0];
+            int nextY = y + d[1];
+            // 超过边界
+            if (nextX < 0 || nextX >= grid.length || nextY < 0 || nextY >= grid[0].length) continue;
+            // 不符合条件，不继续遍历
+            if (grid[nextX][nextY] == 0 || grid[nextX][nextY] == 2) continue;
+            dfs(grid, nextX, nextY);
+        }
+    }
+
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        int n = scanner.nextInt();
+        int m = scanner.nextInt();
+        int[][] grid = new int[n][m];
+
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < m; j++) {
+                grid[i][j] = scanner.nextInt();
+            }
+        }
+
+        // 步骤一：
+        // 从左侧边，和右侧边 向中间遍历
+        for (int i = 0; i < n; i++) {
+            if (grid[i][0] == 1) dfs(grid, i, 0);
+            if (grid[i][m - 1] == 1) dfs(grid, i, m - 1);
+        }
+
+        // 从上边和下边 向中间遍历
+        for (int j = 0; j < m; j++) {
+            if (grid[0][j] == 1) dfs(grid, 0, j);
+            if (grid[n - 1][j] == 1) dfs(grid, n - 1, j);
+        }
+
+        // 步骤二、步骤三
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < m; j++) {
+                if (grid[i][j] == 1) grid[i][j] = 0;
+                if (grid[i][j] == 2) grid[i][j] = 1;
+            }
+        }
+
+        for (int i = 0; i < n; i++) {
+            for (int j = 0; j < m; j++) {
+                System.out.print(grid[i][j] + " ");
+            }
+            System.out.println();
+        }
+        
+        scanner.close();
+    }
+}
+
+
+```
+
+
 ### Python
 
+```python
+
+def dfs(grid, x, y):
+    grid[x][y] = 2
+    directions = [(-1, 0), (0, -1), (1, 0), (0, 1)]  # 四个方向
+    for dx, dy in directions:
+        nextx, nexty = x + dx, y + dy
+        # 超过边界
+        if nextx < 0 or nextx >= len(grid) or nexty < 0 or nexty >= len(grid[0]):
+            continue
+        # 不符合条件，不继续遍历
+        if grid[nextx][nexty] == 0 or grid[nextx][nexty] == 2:
+            continue
+        dfs(grid, nextx, nexty)
+
+def main():
+    n, m = map(int, input().split())
+    grid = [[int(x) for x in input().split()] for _ in range(n)]
+
+    # 步骤一：
+    # 从左侧边，和右侧边 向中间遍历
+    for i in range(n):
+        if grid[i][0] == 1:
+            dfs(grid, i, 0)
+        if grid[i][m - 1] == 1:
+            dfs(grid, i, m - 1)
+
+    # 从上边和下边 向中间遍历
+    for j in range(m):
+        if grid[0][j] == 1:
+            dfs(grid, 0, j)
+        if grid[n - 1][j] == 1:
+            dfs(grid, n - 1, j)
+
+    # 步骤二、步骤三
+    for i in range(n):
+        for j in range(m):
+            if grid[i][j] == 1:
+                grid[i][j] = 0
+            if grid[i][j] == 2:
+                grid[i][j] = 1
+
+    # 打印结果
+    for row in grid:
+        print(' '.join(map(str, row)))
+
+if __name__ == "__main__":
+    main()
+
+```
+
+
 ### Go
 
 ### Rust