Create 894-all-possible-full-binary-trees.js

Author: everthis

894-all-possible-full-binary-trees.js

@@ -0,0 +1,35 @@
+/**
+ * Definition for a binary tree node.
+ * function TreeNode(val) {
+ *     this.val = val;
+ *     this.left = this.right = null;
+ * }
+ */
+/**
+ * @param {number} N
+ * @return {TreeNode[]}
+ */
+const allPossibleFBT = function(N) {
+  if (N <= 0) {
+    return []
+  }
+  const dp = new Array(N + 1)
+  for (let i = 0; i <= N; i++) {
+    dp[i] = []
+  }
+  dp[1].push(new TreeNode(0))
+
+  for (let numNode = 1; numNode <= N; numNode += 2) {
+    for (let leftNode = 1; leftNode < numNode; leftNode += 2) {
+      for (let left of dp[leftNode]) {
+        for (let right of dp[numNode - 1 - leftNode]) {
+          let root = new TreeNode(0)
+          root.left = left
+          root.right = right
+          dp[numNode].push(root)
+        }
+      }
+    }
+  }
+  return dp[N]
+};