Create 723-candy-crush.js

Author: everthis

723-candy-crush.js

@@ -0,0 +1,84 @@
+/**
+ * @param {number[][]} board
+ * @return {number[][]}
+ */
+const candyCrush = function (board) {
+  while (true) {
+    let moreToCrush = false
+    for (let i = 0; i < board.length; i++) {
+      for (let j = 0; j < board[0].length; j++) {
+        if (board[i][j] > 0) {
+          moreToCrush =
+            flagForCrush(board, i, j, board[i][j], 0, true, false) ||
+            moreToCrush
+          moreToCrush =
+            flagForCrush(board, i, j, board[i][j], 0, false, true) ||
+            moreToCrush
+        }
+      }
+    }
+    if (!moreToCrush) break
+    crush(board)
+    inflictGravity(board)
+  }
+  return board
+}
+const flagForCrush = function (board, i, j, target, count, right, down) {
+  if (
+    j === board[0].length ||
+    i === board.length ||
+    Math.abs(board[i][j]) !== Math.abs(target)
+  ) {
+    return count >= 3
+  }
+
+  let shouldFlagIndexRight = flagForCrush(
+    board,
+    i,
+    j + 1,
+    target,
+    right ? count + 1 : 1,
+    true,
+    false
+  )
+  let shouldFlagIndexDown = flagForCrush(
+    board,
+    i + 1,
+    j,
+    target,
+    down ? count + 1 : 1,
+    false,
+    true
+  )
+
+  if ((shouldFlagIndexRight && right) || (shouldFlagIndexDown && down)) {
+    board[i][j] = -Math.abs(board[i][j])
+    return true
+  }
+
+  return false
+}
+const crush = function (board) {
+  for (let i = 0; i < board.length; i++) {
+    for (let j = 0; j < board[0].length; j++) {
+      if (board[i][j] < 0) board[i][j] = 0
+    }
+  }
+}
+const inflictGravity = function (board) {
+  for (let j = 0; j < board[0].length; j++) {
+    let st = board.length - 1
+    let end = board.length - 2
+    while (end >= 0) {
+      if (board[st][j] === 0 && board[end][j] !== 0) {
+        let temp = board[st][j]
+        board[st][j] = board[end][j]
+        board[end][j] = temp
+        st--
+      } else if (board[st][j] !== 0) {
+        st--
+      }
+      end--
+    }
+  }
+}