NodeDepth Algrothmic

NodeDepth

class TreeNode {
    val: number
    left: TreeNode | null
    right: TreeNode | null
    constructor(val?: number, left?: TreeNode | null, right?: TreeNode | null) {
        this.val = (val===undefined ? 0 : val)
        this.left = (left===undefined ? null : left)
        this.right = (right===undefined ? null : right)
    }
}


interface stackShape{
  node:TreeNode,
  depth:number
}

// time= O(n) s(h) wich h is the length of the tree
function NodeDepth(root:TreeNode):number{
  let sumDepth=0
  let stack:[stackShape]=[{node:root,depth:0}]
  while(stack.length > 0){
    const {node,depth}=stack.pop()!
    if(!node)continue ;
    sumDepth+=depth
    if(node.left){
    stack.push({node:node.left,depth:depth+1})
    }
    if(node.right){
      stack.push({node:node.right,depth:depth+1})
    }
  }
return sumDepth

}