Update README.md

Author: yanglbme

solution/1500-1599/1568.Minimum Number of Days to Disconnect Island/README.md

@@ -295,6 +295,71 @@ func minDays(grid [][]int) int {
 }
 ```
 
+#### JavaScript
+
+```js
+/**
+ * @param {number[][]} grid
+ * @return {number}
+ */
+var minDays = function (grid) {
+    const directions = [
+        [0, 1],
+        [1, 0],
+        [0, -1],
+        [-1, 0],
+    ];
+    const rows = grid.length;
+    const cols = grid[0].length;
+
+    function dfs(x, y, visited) {
+        visited[x][y] = true;
+        for (let [dx, dy] of directions) {
+            const nx = x + dx,
+                ny = y + dy;
+            if (
+                nx >= 0 &&
+                ny >= 0 &&
+                nx < rows &&
+                ny < cols &&
+                grid[nx][ny] === 1 &&
+                !visited[nx][ny]
+            ) {
+                dfs(nx, ny, visited);
+            }
+        }
+    }
+
+    function countIslands() {
+        let visited = Array.from({ length: rows }, () => Array(cols).fill(false));
+        let count = 0;
+        for (let i = 0; i < rows; i++) {
+            for (let j = 0; j < cols; j++) {
+                if (grid[i][j] === 1 && !visited[i][j]) {
+                    count++;
+                    dfs(i, j, visited);
+                }
+            }
+        }
+        return count;
+    }
+
+    if (countIslands() !== 1) return 0;
+
+    for (let i = 0; i < rows; i++) {
+        for (let j = 0; j < cols; j++) {
+            if (grid[i][j] === 1) {
+                grid[i][j] = 0;
+                if (countIslands() !== 1) return 1;
+                grid[i][j] = 1;
+            }
+        }
+    }
+
+    return 2;
+};
+```
+
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 <!-- solution:end -->