1.二叉树结构体

struct TreeNode { int val; TreeNode *left; TreeNode *right; TreeNode(int x) : val(x), left(NULL), right(NULL) {} };

2.二叉树初始化

TreeNode* initBTree(vector<int> elements) { int eleSize; eleSize = elements.size(); if (eleSize < 1) { return NULL; } //动态申请size大小的指针数组 TreeNode **nodes = new TreeNode*[eleSize]; //将int数据转换为TreeNode节点 for (int i = 0; i < eleSize; i++) { if (elements[i] == 0) { nodes[i] = NULL; } else { nodes[i] = new TreeNode(elements[i]); } } queue<TreeNode*> nodeQueue; nodeQueue.push(nodes[0]); TreeNode *node; int index = 1; while (index < eleSize) { node = nodeQueue.front(); nodeQueue.pop(); nodeQueue.push(nodes[index++]); node->left = nodeQueue.back(); nodeQueue.push(nodes[index++]); node->right = nodeQueue.back(); } return nodes[0]; }

3.二叉树对称性判断

bool isCheak(TreeNode* p, TreeNode* q) { if (!p && !q) return true; if (!p || !q) return false; return p->val == q->val && isCheak(p->left, p->right) && isCheak(p->right, p->left); } bool isSymmetric(TreeNode* root) { return isCheak(root, root); }

4.测试程序

void testIsSymmetric101() { vector<int> arr = { 1, 2, 2, 3, 4, 4, 3 }; TreeNode* root = initBTree(arr); Solution101 sol; bool result = sol.isSymmetric(root); cout << "result = " << result << endl; }```