/**
* Definition for a binary tree node.
* type TreeNode struct {
* Val int
* Left *TreeNode
* Right *TreeNode
* }
*/
import "strconv"
func tree2str(t *TreeNode) string {
if t == nil {
return ""
}
left, right := tree2str(t.Left), tree2str(t.Right)
str := strconv.Itoa(t.Val)
if left != "" || left == "" && right != "" {
str += "(" + left + ")"
}
if right != "" {
str += "(" + right + ")"
}
return str
}