在 C++ 中查找二叉树克隆中的对应节点
c++server side programmingprogramming
假设我们有两个二叉树,一个是原始二叉树,另一个是克隆二叉树,并给出了对原始树中节点目标的引用。克隆树实际上是原始树的副本。我们必须在克隆树中找到对同一节点的引用。
因此,如果树如下所示,目标是 3,则输出将为 3。
为了解决这个问题,我们将遵循以下步骤 −
定义一个名为solve()的方法,它将获取node1m node2和target
如果node1为null,则返回null
如果node1是target并且node 1的值是node2的值,则返回node2
leftPart := resolve(left of node1, left of node2, target)
rightPart := resolve(right of node1, right of node2, target)
如果leftPart不为null,则返回leftPart,否则返回rightPart
从主方法调用返回solve(original, cloned, target)
示例 (C++)
让我们看下面的实现,以便更好地理解 −
#include <bits/stdc++.h> using namespace std; class TreeNode{ public: int val; TreeNode *left, *right; TreeNode(int data){ val = data; left = right = NULL; } }; void insert(TreeNode **root, int val){ queue<TreeNode*> q; q.push(*root); while(q.size()){ TreeNode *temp = q.front(); q.pop(); if(!temp->left){ if(val != NULL) temp->left = new TreeNode(val); else temp->left = new TreeNode(0); return; } else { q.push(temp->left); } if(!temp->right){ if(val != NULL) temp->right = new TreeNode(val); else temp->right = new TreeNode(0); return; } else { q.push(temp->right); } } } TreeNode *make_tree(vector<int> v){ TreeNode *root = new TreeNode(v[0]); for(int i = 1; i<v.size(); i++){ insert(&root, v[i]); } return root; } class Solution { public: TreeNode* solve(TreeNode* node1, TreeNode* node2, TreeNode* target){ if(!node1) return NULL; if(node1 == target && node1->val == node2->val) return node2; TreeNode* leftPart = solve(node1->left, node2->left, target); TreeNode* rightPart = solve(node1->right, node2->right, target); return leftPart? leftPart : rightPart; } TreeNode* getTargetCopy(TreeNode* original, TreeNode* cloned, TreeNode* target) { return solve(original, cloned, target); } }; main(){ vector<int> v = {7,4,3,NULL,NULL,6,19}; TreeNode *root = make_tree(v); TreeNode *cloned = make_tree(v); TreeNode *target = root->right; //The node with value 3 Solution ob; cout << (ob.getTargetCopy(root, cloned, target))->val; }
输入
[7,4,3,null,null,6,19] 3
输出
3