呀，天亮了
Aug 15, 2020 07:22:21 AM
https://leetcode.com/problems/remove-duplicates-from-sorted-list-ii/
Given a sorted linked list, delete all nodes that have duplicate numbers, leaving only distinct numbers from the original list.
Return the linked list sorted as well.
Example 1:
Input: 1->2->3->3->4->4->5 Output: 1->2->5
Example 2:
Input: 1->1->1->2->3 Output: 2->3
Aug 11, 2020 02:19:48 AM
https://leetcode.com/problems/plus-one-linked-list/
Given a non-negative integer represented as non-empty a singly linked list of digits, plus one to the integer.
You may assume the integer do not contain any leading zero, except the number 0 itself.
The digits are stored such that the most significant digit is at the head of the list.
Example :
Input: [1,2,3] Output: [1,2,4]
Jul 29, 2020 01:21:45 AM
https://leetcode.com/problems/task-scheduler/
You are given a char array representing tasks CPU need to do. It contains capital letters A to Z where each letter represents a different task. Tasks could be done without the original order of the array. Each task is done in one unit of time. For each unit of time, the CPU could complete either one task or just be idle.
However, there is a non-negative integer n that represents the cooldown period between two same tasks (the same letter in the array), that is that there must be at least n units of time between any two same tasks.
You need to return the least number of units of times that the CPU will take to finish all the given tasks.
Example 1:
Input: tasks = ["A","A","A","B","B","B"], n = 2 Output: 8 Explanation: A -> B -> idle -> A -> B -> idle -> A -> B There is at least 2 units of time between any two same tasks.
Example 2:
Input: tasks = ["A","A","A","B","B","B"], n = 0 Output: 6 Explanation: On this case any permutation of size 6 would work since n = 0. ["A","A","A","B","B","B"] ["A","B","A","B","A","B"] ["B","B","B","A","A","A"] ... And so on.
Example 3:
Input: tasks = ["A","A","A","A","A","A","B","C","D","E","F","G"], n = 2 Output: 16 Explanation: One possible solution is A -> B -> C -> A -> D -> E -> A -> F -> G -> A -> idle -> idle -> A -> idle -> idle -> A
Constraints:
[1, 10000].n is in the range [0, 100].
Jul 23, 2020 08:28:32 AM
https://leetcode.com/problems/top-k-frequent-elements/
Given a non-empty array of integers, return the k most frequent elements.
Example 1:
Input: nums = [1,1,1,2,2,3], k = 2 Output: [1,2]
Example 2:
Input: nums = [1], k = 1 Output: [1]
Jul 15, 2020 06:51:25 AM
https://leetcode.com/problems/minimum-increment-to-make-array-unique/
Given an array of integers A, a move consists of choosing any A[i], and incrementing it by 1.
Return the least number of moves to make every value in A unique.
Example 1:
Input: [1,2,2] Output: 1 Explanation: After 1 move, the array could be [1, 2, 3].
Example 2:
Input: [3,2,1,2,1,7] Output: 6 Explanation: After 6 moves, the array could be [3, 4, 1, 2, 5, 7]. It can be shown with 5 or less moves that it is impossible for the array to have all unique values.
Jul 15, 2020 02:33:33 AM
https://leetcode.com/problems/unique-email-addresses/
Every email consists of a local name and a domain name, separated by the @ sign.
For example, in alice@leetcode.com, alice is the local name, and leetcode.com is the domain name.
Besides lowercase letters, these emails may contain '.'s or '+'s.
If you add periods ('.') between some characters in the local name part of an email address, mail sent there will be forwarded to the same address without dots in the local name. For example, "alice.z@leetcode.com" and "alicez@leetcode.com" forward to the same email address. (Note that this rule does not apply for domain names.)
If you add a plus ('+') in the local name, everything after the first plus sign will be ignored. This allows certain emails to be filtered, for example m.y+name@email.com will be forwarded to my@email.com. (Again, this rule does not apply for domain names.)
It is possible to use both of these rules at the same time.
Given a list of emails, we send one email to each address in the list. How many different addresses actually receive mails?
Example 1:
Input: ["test.email+alex@leetcode.com","test.e.mail+bob.cathy@leetcode.com","testemail+david@lee.tcode.com"] Output: 2 Explanation: "testemail@leetcode.com" and "testemail@lee.tcode.com" actually receive mails
Jul 15, 2020 01:29:39 AM
https://leetcode.com/problems/angle-between-hands-of-a-clock/
Given two numbers, hour and minutes. Return the smaller angle (in degrees) formed between the hour and the minute hand.
Example 1:
Input: hour = 12, minutes = 30 Output: 165
Jul 14, 2020 08:43:09 AM
https://leetcode.com/problems/third-maximum-number/
Given a non-empty array of integers, return the third maximum number in this array. If it does not exist, return the maximum number. The time complexity must be in O(n).
Example 1:
Input: [3, 2, 1] Output: 1 Explanation: The third maximum is 1.
Jul 14, 2020 08:20:21 AM
https://leetcode.com/problems/height-checker/
Students are asked to stand in non-decreasing order of heights for an annual photo.
Return the minimum number of students that must move in order for all students to be standing in non-decreasing order of height.
Notice that when a group of students is selected they can reorder in any possible way between themselves and the non selected students remain on their seats.
Example 1:
Input: heights = [1,1,4,2,1,3] Output: 3 Explanation: Current array : [1,1,4,2,1,3] Target array : [1,1,1,2,3,4] On index 2 (0-based) we have 4 vs 1 so we have to move this student. On index 4 (0-based) we have 1 vs 3 so we have to move this student. On index 5 (0-based) we have 3 vs 4 so we have to move this student.
Jul 14, 2020 06:06:00 AM
https://leetcode.com/problems/sort-array-by-parity/
Given an array A of non-negative integers, return an array consisting of all the even elements of A, followed by all the odd elements of A.
You may return any answer array that satisfies this condition.
Example 1:
Input: [3,1,2,4] Output: [2,4,3,1] The outputs [4,2,3,1], [2,4,1,3], and [4,2,1,3] would also be accepted.
