꿈꾸는공학도

https://leetcode.com/problems/minimum-string-length-after-removing-substrings/description/?envType=daily-question&envId=2024-10-07You are given a string s consisting only of uppercase English letters.You can apply some operations to this string where, in one operation, you can remove any occurrence of one of the substrings "AB" or "CD" from s.Return the minimum possible length of the resulting s..

https://leetcode.com/problems/jewels-and-stones/description/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:I..

https://leetcode.com/problems/my-calendar-i/description/?envType=daily-question&envId=2024-09-26You are implementing a program to use as your calendar. We can add a new event if adding the event will not cause a double booking.A double booking happens when two events have some non-empty intersection (i.e., some moment is common to both events.).The event can be represented as a pair of integers ..

https://leetcode.com/problems/sum-of-prefix-scores-of-strings/description/?envType=daily-question&envId=2024-09-25You are given an array words of size n consisting of non-empty strings.We define the score of a string word as the number of strings words[i] such that word is a prefix of words[i].For example, if words = ["a", "ab", "abc", "cab"], then the score of "ab" is 2, since "ab" is a prefix ..

https://leetcode.com/problems/count-good-nodes-in-binary-tree/Given a binary tree root, a node X in the tree is named good if in the path from root to X there are no nodes with a value greater than X.Return the number of good nodes in the binary tree. Example 1:Input: root = [3,1,4,3,null,1,5]Output: 4Explanation: Nodes in blue are good.Root Node (3) is always a good node.Node 4 -> (3,4) is the ..

https://leetcode.com/problems/number-of-good-leaf-nodes-pairs/description/You are given the root of a binary tree and an integer distance. A pair of two different leaf nodes of a binary tree is said to be good if the length of the shortest path between them is less than or equal to distance.Return the number of good leaf node pairs in the tree. Example 1:Input: root = [1,2,3,null,4], distance = ..

https://leetcode.com/problems/delete-nodes-from-linked-list-present-in-array/description/You are given an array of integers nums and the head of a linked list. Return the head of the modified linked list after removing all nodes from the linked list that have a value that exists in nums. Example 1:Input: nums = [1,2,3], head = [1,2,3,4,5]Output: [4,5]Explanation:Remove the nodes with values 1, 2..

Given an array of integers nums, sort the array in increasing order based on the frequency of the values. If multiple values have the same frequency, sort them in decreasing order.Return the sorted array. Example 1:Input: nums = [1,1,2,2,2,3]Output: [3,1,1,2,2,2]Explanation: '3' has a frequency of 1, '1' has a frequency of 2, and '2' has a frequency of 3.Example 2:Input: nums = [2,3,1,3,2]Output..

https://leetcode.com/problems/sum-of-digits-of-string-after-convert/description/?envType=daily-question&envId=2024-09-03You are given a string s consisting of lowercase English letters, and an integer k.First, convert s into an integer by replacing each letter with its position in the alphabet (i.e., replace 'a' with 1, 'b' with 2, ..., 'z' with 26). Then, transform the integer by replacing it w..

https://leetcode.com/problems/best-time-to-buy-and-sell-stock-ii/description/You are given an integer array prices where prices[i] is the price of a given stock on the ith day.On each day, you may decide to buy and/or sell the stock. You can only hold at most one share of the stock at any time. However, you can buy it then immediately sell it on the same day.Find and return the maximum profit yo..