Create 1568-minimum-number-of-days-to-disconnect-island.js

Author: everthis

1568-minimum-number-of-days-to-disconnect-island.js

@@ -0,0 +1,38 @@
+/**
+ * @param {number[][]} grid
+ * @return {number}
+ */
+const minDays = function (grid) {
+  if (!grid.length || !grid[0].length) return 0
+  if (numIslands(grid) != 1) return 0
+  for (let i = 0; i < grid.length; i++) {
+    for (let j = 0; j < grid[0].length; j++) {
+      if (grid[i][j] == 1) {
+        grid[i][j] = 0
+        if (numIslands(grid) != 1) return 1
+        grid[i][j] = 1
+      }
+    }
+  }
+  return 2
+}
+
+function numIslands(grid) {
+  let m = Array.from({ length: grid.length }, (v, i) => {
+    return [...grid[i]]
+  })
+  let count = 0
+  for (let i = 0; i < m.length; i++)
+    for (let j = 0; j < m[0].length; j++) removeIslandAt(i, j, 1)
+  return count
+  function removeIslandAt(i, j, firstIteration = 0) {
+    if (i >= m.length || j >= m[0].length || i < 0 || j < 0 || m[i][j] == 0)
+      return
+    m[i][j] = 0
+    count += firstIteration
+    removeIslandAt(i - 1, j)
+    removeIslandAt(i + 1, j)
+    removeIslandAt(i, j - 1)
+    removeIslandAt(i, j + 1)
+  }
+}