Leetcode-construct Binary Tree from preorder and inorder traversal

Given Preorder and inorder traversal of a tree, construct the binary tree.

Note:

Assume that duplicates does not exist in the tree.

Class Solution {Private:treenode *root;    Vector<int> Mypreorder; Vector<int> myinorder;public:treenode *createtree (TreeNode *root,int pre,int in,int lenth) {int l,r,r        Ootpos;        if (lenth<=0) root=null;                        else {//new node Root=new TreeNode (Mypreorder[pre]); Find root for (int i=in;i<=in+lenth-1;i++) if (Root->val==myinorder[i]) rootpo                        S=i;            Sub-tree length l=rootpos-in;                        R=LENTH-L-1;            Build subtree Root->left=createtree (root->left,pre+1,in,l);        Root->right=createtree (Root->right, pre+1+l,rootpos+1,r);    } return root; } TreeNode *buildtree (vector<int> &preorder, vector<int> &inorder) {if (Preorder.size () &                lt;=0) return NULL;        Copy Mypreorder=preorder;          Myinorder=inorder;      Build Root=createtree (Root,0,0,preorder.size ());    return root; }};

Leetcode-construct Binary Tree from preorder and inorder traversal