add sol

leetcode/leetcode75/BinaryTree-DFS/1448.CountGoodNodesInBinaryTree/CountGoodNodesInBinaryTree.go

@@ -0,0 +1,93 @@
+package main
+
+import (
+	"fmt"
+)
+
+/**
+ * Definition for a binary tree node.
+ * type TreeNode struct {
+ *     Val int
+ *     Left *TreeNode
+ *     Right *TreeNode
+ * }
+ */
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func goodNodes(root *TreeNode) int {
+	cnt := 0
+	var dfs func(*TreeNode, int)
+	dfs = func(root *TreeNode, mx int) {
+		if root == nil {
+			return
+		}
+		if mx <= root.Val {
+			cnt++
+			mx = root.Val
+		}
+
+		dfs(root.Left, mx)
+		dfs(root.Right, mx)
+	}
+
+	dfs(root, -10001)
+	return cnt
+}
+
+func goodNodes1(root *TreeNode) int {
+	return rec(root.Left, root.Right, root.Val) + 1
+}
+
+func rec(rootLeft *TreeNode, rootRight *TreeNode, mx int) int {
+	cnt := 0
+
+	if rootLeft != nil && rootLeft.Val >= mx {
+		cnt++
+	}
+	if rootLeft != nil {
+		cnt += rec(rootLeft.Left, rootLeft.Right, max(mx, rootLeft.Val))
+	}
+
+	if rootRight != nil && rootRight.Val >= mx {
+		cnt++
+	}
+	if rootRight != nil {
+		cnt += rec(rootRight.Left, rootRight.Right, max(mx, rootRight.Val))
+	}
+
+	return cnt
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
+func main() {
+	// Define the trees
+	root := &TreeNode{
+		Val: 3,
+		Left: &TreeNode{
+			Val:  1,
+			Left: &TreeNode{Val: 3},
+		},
+		Right: &TreeNode{
+			Val: 4,
+			Left: &TreeNode{
+				Val:  4,
+				Left: &TreeNode{Val: 1},
+			},
+			Right: &TreeNode{Val: 5},
+		},
+	}
+
+	// Check leaf similarity
+	fmt.Println(goodNodes1(root))
+}