[LeetCode] Cells in a Range on an Excel Sheet

2194. Cells in a Range on an Excel Sheet

A cell (r, c) of an excel sheet is represented as a string ““ where:

  • denotes the column number c of the cell. It is represented by alphabetical letters.
  • For example, the 1st column is denoted by ‘A’, the 2nd by ‘B’, the 3rd by ‘C’, and so on.
  • is the row number r of the cell. The rth row is represented by the integer r.

You are given a string s in the format “:“, where represents the column c1, represents the row r1, represents the column c2, and represents the row r2, such that r1 <= r2 and c1 <= c2.

Return the list of cells (x, y) such that r1 <= x <= r2 and c1 <= y <= c2. The cells should be represented as strings in the format mentioned above and be sorted in non-decreasing order first by columns and then by rows.

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[LeetCode] Append K Integers With Minimal Sum

2195. Append K Integers With Minimal Sum

You are given an integer array nums and an integer k. Append k unique positive integers that do not appear in nums to nums such that the resulting total sum is minimum.

Return the sum of the k integers appended to nums

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[LeetCode] Create Binary Tree From Descriptions

2196. Create Binary Tree From Descriptions

You are given a 2D integer array descriptions where descriptions[i] = [parenti, childi, isLefti] indicates that parenti is the parent of childi in a binary tree of unique values. Furthermore,

  • If isLefti == 1, then childi is the left child of parenti.
  • If isLefti == 0, then childi is the right child of parenti.

Construct the binary tree described by descriptions and return its root.

The test cases will be generated such that the binary tree is valid.

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[LeetCode] Replace Non-Coprime Numbers in Array

2197. Replace Non-Coprime Numbers in Array

You are given an array of integers nums. Perform the following steps:

  1. Find any two adjacent numbers in nums that are non-coprime.
  2. If no such numbers are found, stop the process.
  3. Otherwise, delete the two numbers and replace them with their LCM (Least Common Multiple).
  4. Repeat this process as long as you keep finding two adjacent non-coprime numbers.

Return the final modified array. It can be shown that replacing adjacent non-coprime numbers in any arbitrary order will lead to the same result.

The test cases are generated such that the values in the final array are less than or equal to 108.

Two values x and y are non-coprime if GCD(x, y) > 1 where GCD(x, y) is the Greatest Common Divisor of x and y.

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[LeetCode] Count All Valid Pickup and Delivery Options

1359. Count All Valid Pickup and Delivery Options

Given n orders, each order consist in pickup and delivery services.

Count all valid pickup/delivery possible sequences such that delivery(i) is always after of pickup(i).

Since the answer may be too large, return it modulo 10^9 + 7.

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[LeetCode] Most Frequent Number Following Key In an Array

2190. Most Frequent Number Following Key In an Array

You are given a 0-indexed integer array nums. You are also given an integer key, which is present in nums.

For every unique integer target in nums, count the number of times target immediately follows an occurrence of key in nums. In other words, count the number of indices i such that:

  • 0 <= i <= n - 2,
  • nums[i] == key and,
  • nums[i + 1] == target.

Return the target with the maximum count. The test cases will be generated such that the target with maximum count is unique.

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[LeetCode] Sort the Jumbled Numbers

2191. Sort the Jumbled Numbers

You are given a 0-indexed integer array mapping which represents the mapping rule of a shuffled decimal system. mapping[i] = j means digit i should be mapped to digit j in this system.

The mapped value of an integer is the new integer obtained by replacing each occurrence of digit i in the integer with mapping[i] for all 0 <= i <= 9.

You are also given another integer array nums. Return the array nums sorted in non-decreasing order based on the mapped values of its elements.

Notes:

  • Elements with the same mapped values should appear in the same relative order as in the input.
  • The elements of nums should only be sorted based on their mapped values and not be replaced by them.
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[LeetCode] Minimum Number of Moves to Make Palindrome

2193. Minimum Number of Moves to Make Palindrome

You are given a string s consisting only of lowercase English letters.

In one move, you can select any two adjacent characters of s and swap them.

Return the minimum number of moves needed to make s a palindrome.

Note that the input will be generated such that s can always be converted to a palindrome.

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[LeetCode] All Ancestors of a Node in a Directed Acyclic Graph

2192. All Ancestors of a Node in a Directed Acyclic Graph

You are given a positive integer n representing the number of nodes of a Directed Acyclic Graph (DAG). The nodes are numbered from 0 to n - 1 (inclusive).

You are also given a 2D integer array edges, where edges[i] = [fromi, toi] denotes that there is a unidirectional edge from fromi to toi in the graph.

Return a list answer, where answer[i] is the list of ancestors of the ith node, sorted in ascending order.

A node u is an ancestor of another node v if u can reach v via a set of edges.

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13th Place on LeetCode Weekly Contest

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