1457. Pseudo-Palindromic Paths in a Binary Tree

-

class Solution{

public:

  int pseudoPalindromicPaths(TreeNode *root, int count = 0){

    // dfs way to find the number of pseudo palindromic paths

    if (!root)

      return 0;

    count ^= 1 << root->val;

    int res = pseudoPalindromicPaths(root->left, count) + pseudoPalindromicPaths(root->right, count);

    if (!root->left && !root->right && (count & (count - 1)) == 0)

      res++;

    return res;

  }

};

Comments

Post a Comment

Popular posts from this blog

1431. Kids With the Greatest Number of Candies

-
Question There are n kids with candies. You are given an integer array candies, where each candies[i] represents the number of candies the ith kid has, and an integer extraCandies, denoting the number of extra candies that you have. Return a boolean array result of length n, where result[i] is true if, after giving the ith kid all the extraCandies, they will have the greatest number of candies among all the kids, or false otherwise. Note that multiple kids can have the greatest number of candies. Example 1: Input: candies = [2,3,5,1,3], extraCandies = 3 Output: [true,true,true,false,true] Explanation: If you give all extraCandies to: - Kid 1, they will have 2 + 3 = 5 candies, which is the greatest among the kids. - Kid 2, they will have 3 + 3 = 6 candies, which is the greatest among the kids. - Kid 3, they will have 5 + 3 = 8 candies, which is the greatest among the kids. - Kid 4, they will have 1 + 3 = 4 candies, which is not the greatest among the kids. - Kid 5, they will have 3 ...
Read more

125. Valid Palindrome

-
A phrase is a palindrome if it reads the same forwards and backwards after converting all uppercase letters to lowercase and removing all non-alphanumeric characters. Alphanumeric characters include letters and numbers. If the string s is given, returns true if it is a palindrome, or false otherwise. Example 1: Input: s = "Man, Plan, Channel: Panama" Output: true Explanation: "amanaplanacanalpanama" is a palindrome. Example 2: Input: s = "car race" Output: false Explanation: "raceacar" is not a palindrome. Example 3: Input: s = " " Output: true Explanation: s is the empty string "" after removing non-alphanumeric characters. Since the empty string reads forwards and backwards the same way, it is a palindrome. Limitations: 1
Read more

771. Jewels and Stones

-
Question You're given strings jewels representing the types of stones that are jewels, and stones representing the stones you have. Each character in stones is a type of stone you have. You want to know how many of the stones you have are also jewels. Letters are case sensitive, so "a" is considered a different type of stone from "A". Example 1: Input: jewels = "aA", stones = "aAAbbbb" Output: 3 Example 2: Input: jewels = "z", stones = "ZZ" Output: 0 Solution class Solution { public: int numJewelsInStones(string jewels, string stones) { int d=0; for(int i=0;i
Read more