二叉树层序遍历 之字形遍历问题
简单写一下初级的层序遍历和进阶版层序遍历
void rightSideView(TreeNode* root) { queue<TreeNode*> q; q.push(root); while (!q.empty()) { TreeNode* tmp = q.front(); cout<<"cur val is "<<tmp->val<<endl; q.pop(); if(tmp->left != NULL) q.push(tmp->left); if(tmp->right != NULL) q.push(tmp->right); } }
//20_1117 临时贴一个二叉树层序遍历进阶版(每一层保存在一个数组中,最终是一个二维数组) vector<vector<int>> getTreeNodeFloorPrint(TreeNode* root) { vector<vector<int>> res; if(root == NULL) return res; queue<TreeNode*> q; q.push(root); while (!q.empty()) { int count = 0; int qSize = q.size(); vector<int> tmp; while (count < qSize) { TreeNode* cur = q.front(); q.pop(); tmp.push_back(cur->val); if(cur->left != NULL) q.push(cur->left); if(cur->right != NULL) q.push(cur->right); count++; } res.push_back(tmp); } return res; }