[LeetCode] IPO

502. IPO

Suppose LeetCode will start its IPO soon. In order to sell a good price of its shares to Venture Capital, LeetCode would like to work on some projects to increase its capital before the IPO. Since it has limited resources, it can only finish at most k distinct projects before the IPO. Help LeetCode design the best way to maximize its total capital after finishing at most k distinct projects.

You are given n projects where the ith project has a pure profit profits[i] and a minimum capital of capital[i] is needed to start it.

Initially, you have w capital. When you finish a project, you will obtain its pure profit and the profit will be added to your total capital.

Pick a list of at most k distinct projects from given projects to maximize your final capital, and return the final maximized capital.

The answer is guaranteed to fit in a 32-bit signed integer.

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[LeetCode] Minimum Time For K Virus Variants to Spread

1956. Minimum Time For K Virus Variants to Spread

There are n unique virus variants in an infinite 2D grid. You are given a 2D array points, where points[i] = [xi, yi] represents a virus originating at (xi, yi) on day 0. Note that it is possible for multiple virus variants to originate at the same point.

Every day, each cell infected with a virus variant will spread the virus to all neighboring points in the four cardinal directions (i.e. up, down, left, and right). If a cell has multiple variants, all the variants will spread without interfering with each other.

Given an integer k, return the minimum integer number of days for any point to contain at least k of the unique virus variants.

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[LeetCode] GCD Sort of an Array

1998. GCD Sort of an Array

You are given an integer array nums, and you can perform the following operation any number of times on nums:

  • Swap the positions of two elements nums[i] and nums[j] if gcd(nums[i], nums[j]) > 1 where gcd(nums[i], nums[j]) is the greatest common divisor of nums[i] and nums[j].

Return true if it is possible to sort nums in non-decreasing order using the above swap method, or false otherwise.

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[LeetCode] Best Position for a Service Centre

1515. Best Position for a Service Centre

A delivery company wants to build a new service center in a new city. The company knows the positions of all the customers in this city on a 2D-Map and wants to build the new center in a position such that the sum of the euclidean distances to all customers is minimum.

Given an array positions where positions[i] = [xi, yi] is the position of the ith customer on the map, return the minimum sum of the euclidean distances to all customers.

In other words, you need to choose the position of the service center [xcentre, ycentre] such that the following formula is minimized:

Answers within 10-5 of the actual value will be accepted.

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[LeetCode] Minimum Number of Operations to Make Array Continuous

2009. Minimum Number of Operations to Make Array Continuous

You are given an integer array nums. In one operation, you can replace any element in nums with any integer.

nums is considered continuous if both of the following conditions are fulfilled:

  • All elements in nums are unique.
  • The difference between the maximum element and the minimum element in nums equals nums.length - 1.

For example, nums = [4, 2, 5, 3] is continuous, but nums = [1, 2, 3, 5, 6] is not continuous.

Return the minimum number of operations to make nums continuous.

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[LeetCode] Kth Smallest Product of Two Sorted Arrays

2040. Kth Smallest Product of Two Sorted Arrays

Given two sorted 0-indexed integer arrays nums1 and nums2 as well as an integer k, return the kth (1-based) smallest product of nums1[i] * nums2[j] where 0 <= i < nums1.length and 0 <= j < nums2.length.

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[LeetCode] Maximum Number of Ways to Partition an Array

2025. Maximum Number of Ways to Partition an Array

You are given a 0-indexed integer array nums of length n. The number of ways to partition nums is the number of pivot indices that satisfy both conditions:

  • 1 <= pivot < n
  • nums[0] + nums[1] + … + nums[pivot - 1] == nums[pivot] + nums[pivot + 1] + … + nums[n - 1]

You are also given an integer k. You can choose to change the value of one element of nums to k, or to leave the array unchanged.

Return the maximum possible number of ways to partition nums to satisfy both conditions after changing at most one element.

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[LeetCode] Maximum Number of Tasks You Can Assign

2071. Maximum Number of Tasks You Can Assign

You have n tasks and m workers. Each task has a strength requirement stored in a 0-indexed integer array tasks, with the ith task requiring tasks[i] strength to complete. The strength of each worker is stored in a 0-indexed integer array workers, with the jth worker having workers[j] strength. Each worker can only be assigned to a single task and must have a strength greater than or equal to the task’s strength requirement (i.e., workers[j] >= tasks[i]).

Additionally, you have pills magical pills that will increase a worker’s strength by strength. You can decide which workers receive the magical pills, however, you may only give each worker at most one magical pill.

Given the 0-indexed integer arrays tasks and workers and the integers pills and strength, return the maximum number of tasks that can be completed.

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[LeetCode] Process Restricted Friend Requests

2076. Process Restricted Friend Requests

You are given an integer n indicating the number of people in a network. Each person is labeled from 0 to n - 1.

You are also given a 0-indexed 2D integer array restrictions, where restrictions[i] = [xi, yi] means that person xi and person yi cannot become friends, either directly or indirectly through other people.

Initially, no one is friends with each other. You are given a list of friend requests as a 0-indexed 2D integer array requests, where requests[j] = [uj, vj] is a friend request between person uj and person vj.

A friend request is successful if uj and vj can be friends. Each friend request is processed in the given order (i.e., requests[j] occurs before requests[j + 1]), and upon a successful request, uj and vj become direct friends for all future friend requests.

Return a boolean array result, where each result[j] is true if the jth friend request is successful or false if it is not.

Note: If uj and vj are already direct friends, the request is still successful.

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[LeetCode] Sum of k-Mirror Numbers

2081. Sum of k-Mirror Numbers

A k-mirror number is a positive integer without leading zeros that reads the same both forward and backward in base-10 as well as in base-k.

  • For example, 9 is a 2-mirror number. The representation of 9 in base-10 and base-2 are 9 and 1001 respectively, which read the same both forward and backward.
  • On the contrary, 4 is not a 2-mirror number. The representation of 4 in base-2 is 100, which does not read the same both forward and backward.

Given the base k and the number n, return the sum of the n smallest k-mirror numbers.

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