公共祖先的特定判断方法

gdis5251 · Aug 2, 2021 · ddcd4ff · ddcd4ff
1 parent 1f8417b
commit ddcd4ff
Showing 1 changed file with 30 additions and 0 deletions.
diff --git a/精选/04.08.首个共同祖先/main.go b/精选/04.08.首个共同祖先/main.go
@@ -0,0 +1,30 @@
+package main
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func lowestCommonAncestor(root *TreeNode, p *TreeNode, q *TreeNode) *TreeNode {
+	if root == nil {
+		return nil
+	}
+
+	if root.Val == p.Val || root.Val == q.Val {
+		return root
+	}
+
+	lNode := lowestCommonAncestor(root.Left, p, q)
+	rNode := lowestCommonAncestor(root.Right, p, q)
+
+	if lNode != nil && rNode != nil {
+		return root
+	}
+
+	if lNode == nil {
+		return rNode
+	}
+
+	return lNode
+}