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package index
import "math"
func countNodes(root *TreeNode) int {	return countNodesDepth(root, -1, -1)}
func countNodesDepth(root *TreeNode, leftDepth int, rightDepth int) int {	if root == nil {		return 0	}
	var left = 0
	var right = 0
	var curNode = root
	if leftDepth > 0 {
		left = leftDepth	} else {
		for curNode != nil {
			left++			curNode = curNode.Left		}
	}	curNode = root
	if rightDepth > 0 {
		right = rightDepth	} else {
		for curNode != nil {
			right++			curNode = curNode.Right		}
	}
	if left == right {
		return int(math.Pow(2, float64(left))) - 1	}
	return (1 + countNodesDepth(root.Left, left-1, -1) + countNodesDepth(root.Right, -1, right-1))
}