剑指offer —— 重建二叉树 about fe-learning HOT 1 OPEN

var buildTree = function(preorder, inorder) {
    if(preorder.length === 0 || inorder.length === 0) return null
    const root = new TreeNode(preorder[0])
    const i = inorder.indexOf(preorder[0])
    // 递归构建左右子树
    root.left = buildTree(preorder.slice(1, i + 1), inorder.slice(0, i))
    root.right = buildTree(preorder.slice(i + 1), inorder.slice(i + 1))
    return root
};