添加新题目

二叉树/二叉树的直径/main.go

@@ -0,0 +1,28 @@
+package main
+
+type TreeNode struct {
+	Val   int
+	Left  *TreeNode
+	Right *TreeNode
+}
+
+func main() {
+
+}
+
+func diameterOfBinaryTree(root *TreeNode) int {
+	a, b := maxpath(root.Right)
+	c, d := maxpath(root.Left)
+	return max(a+b, c, d)
+}
+
+func maxpath(p *TreeNode) (int, int) {
+	if p == nil {
+		return 0, 0
+	}
+	leftpathnum, leftcurmax := maxpath(p.Left)
+	rightpathnum, rightcurmax := maxpath(p.Right)
+	curmax := max(leftpathnum+rightpathnum, leftcurmax, rightcurmax)
+
+	return 1 + max(leftpathnum+rightpathnum), curmax
+}