Golang leetcode 513. Find Bottom Left Tree Value.go

type TreeNode struct {
	Val   int
	Left  *TreeNode
	Right *TreeNode
}
var maxd, val int

func findBottomLeftValue(root *TreeNode) int {
	maxd = 0
	val = 0
	dfs(root, 1)
	return val
}

func dfs(root *TreeNode, d int) {
	if root == nil {
		return
	}
	if d > maxd {
		maxd = d
		val = root.Val
	}
	if root.Left != nil {
		dfs(root.Left, d+1)
	}
	if root.Right != nil {
		dfs(root.Right, d+1)
	}

}