Today I have done leetcode's January LeetCoding Challenge with cpp.

January LeetCoding Challenge 9

Description

Leaf-Similar Trees

Consider all the leaves of a binary tree, from left to right order, the values of those leaves form a leaf value sequence.

For example, in the given tree above, the leaf value sequence is (6, 7, 4, 9, 8).

Two binary trees are considered leaf-similar if their leaf value sequence is the same.

Return true if and only if the two given trees with head nodes root1 and root2 are leaf-similar.

Example 1:

Input: root1 = [3,5,1,6,2,9,8,null,null,7,4], root2 = [3,5,1,6,7,4,2,null,null,null,null,null,null,9,8]
Output: true

Example 2:

Input: root1 = [1,2,3], root2 = [1,3,2]
Output: false

Constraints:

• The number of nodes in each tree will be in the range [1, 200].
• Both of the given trees will have values in the range [0, 200].

Solution

class Solution {
  void add(TreeNode* node, vector<int> &sequence) {
    if(!node->left && !node->right) {
      sequence.push_back(node->val);
    } else {
      if(node->left) add(node->left, sequence);
      if(node->right) add(node->right, sequence);
    }
  }
public:
  bool leafSimilar(TreeNode* root1, TreeNode* root2) {
    vector<int> seq1, seq2;
    add(root1, seq1);
    add(root2, seq2);
    return seq1 == seq2;
  }
};

// Accepted
// 43/43 cases passed (3 ms)
// Your runtime beats 66.12 % of cpp submissions
// Your memory usage beats 13.67 % of cpp submissions (13.6 MB)