.\623.add-one-row-to-tree ok

侯利朋 · 侯利朋 · commit 68fcbe96ed17 · 2019-08-30T22:01:04.000+08:00
diff --git a/623.add-one-row-to-tree.go b/623.add-one-row-to-tree.go
@@ -0,0 +1,51 @@
+/*
+ * @lc app=leetcode id=623 lang=golang
+ *
+ * [623] Add One Row to Tree
+ */
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+// (44 ms) √ Your runtime beats 94.12 %
+func addOneRow(root *TreeNode, v int, d int) *TreeNode {
+	// if root == nil { 题目要求非空
+	//     return root
+	// }
+	if d == 1 {
+		return &TreeNode{
+			Val:   v,
+			Left:  root,
+			Right: nil,
+		}
+	}
+	// 找到第d-1层的节点
+	queue := []*TreeNode{}
+	queue = append(queue, root)
+	for len(queue) > 0 {
+		d--
+		if d == 1 {
+			break
+		}
+		size := len(queue)
+		for i := 0; i < size; i++ {
+			node := queue[0]
+			queue = queue[1:]
+			if node.Left != nil {
+				queue = append(queue, node.Left)
+			}
+			if node.Right != nil {
+				queue = append(queue, node.Right)
+			}
+		}
+	}
+	for i := 0; i < len(queue); i++ {
+		queue[i].Left = &TreeNode{v, queue[i].Left, nil}
+		queue[i].Right = &TreeNode{v, nil, queue[i].Right}
+	}
+	return root
+}
