[LeetCode] Strange Printer II

1591. Strange Printer II

There is a strange printer with the following two special requirements:

  • On each turn, the printer will print a solid rectangular pattern of a single color on the grid. This will cover up the existing colors in the rectangle.
  • Once the printer has used a color for the above operation, the same color cannot be used again.

You are given a m x n matrix targetGrid, where targetGrid[row][col] is the color in the position (row, col) of the grid.

Return true if it is possible to print the matrix targetGrid, otherwise, return false.

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[LeetCode] Sort Items by Groups Respecting Dependencies

1203. Sort Items by Groups Respecting Dependencies

There are n items each belonging to zero or one of m groups where group[i] is the group that the i-th item belongs to and it’s equal to -1 if the i-th item belongs to no group. The items and the groups are zero indexed. A group can have no item belonging to it.

Return a sorted list of the items such that:

  • The items that belong to the same group are next to each other in the sorted list.
  • There are some relations between these items where beforeItems[i] is a list containing all the items that should come before the i-th item in the sorted array (to the left of the i-th item).

Return any solution if there is more than one solution and return an empty list if there is no solution.

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[LeetCode] Sort Integers by The Number of 1 Bits

1356. Sort Integers by The Number of 1 Bits

You are given an integer array arr. Sort the integers in the array in ascending order by the number of 1’s in their binary representation and in case of two or more integers have the same number of 1’s you have to sort them in ascending order.

Return the array after sorting it.

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[LeetCode] Find Nearest Right Node in Binary Tree

1602. Find Nearest Right Node in Binary Tree

Given the root of a binary tree and a node u in the tree, return the nearest node on the same level that is to the right of u, or return null if u is the rightmost node in its level.

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[LeetCode] Different Ways to Add Parentheses

241. Different Ways to Add Parentheses

Given a string expression of numbers and operators, return all possible results from computing all the different possible ways to group numbers and operators. You may return the answer in any order.

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[LeetCode] Minimum XOR Sum of Two Arrays

1879. Minimum XOR Sum of Two Arrays

You are given two integer arrays nums1 and nums2 of length n.

The XOR sum of the two integer arrays is (nums1[0] XOR nums2[0]) + (nums1[1] XOR nums2[1]) + … + (nums1[n - 1] XOR nums2[n - 1]) (0-indexed).

  • For example, the XOR sum of [1,2,3] and [3,2,1] is equal to (1 XOR 3) + (2 XOR 2) + (3 XOR 1) = 2 + 0 + 2 = 4.

Rearrange the elements of nums2 such that the resulting XOR sum is minimized.

Return the XOR sum after the rearrangement.

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[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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