js+加树形数据

function traverseTree(node, callback) {
  if (node === null) return;
  callback(node);
  if (node.children) {
    node.children.forEach(child => traverseTree(child, callback));
  }
}

function findNode(node, predicate) {
  if (node === null) return null;
  if (predicate(node)) return node;
  if (node.children) {
    for (let child of node.children) {
      const result = findNode(child, predicate);
      if (result !== null) return result;
    }
  }
  return null;
}

function addChild(parentNode, newNode) {
  if (!parentNode.children) {
    parentNode.children = [];
  }
  parentNode.children.push(newNode);
}

function removeChild(parentNode, childNode) {
  if (!parentNode.children) return;
  const index = parentNode.children.indexOf(childNode);
  if (index > -1) {
    parentNode.children.splice(index, 1);
  }
}

function flattenTree(node, result = []) {
  if (node === null) return result;
  result.push(node);
  if (node.children) {
    node.children.forEach(child => flattenTree(child, result));
  }
  return result;
}

function getTreeDepth(node) {
  if (node === null) return 0;
  let maxDepth = 0;
  if (node.children) {
    node.children.forEach(child => {
      const depth = getTreeDepth(child);
      maxDepth = Math.max(maxDepth, depth);
    });
  }
  return maxDepth + 1;
}