[LeetCode] Maximum Subarray Min-Product

1856. Maximum Subarray Min-Product

The min-product of an array is equal to the minimum value in the array multiplied by the array’s sum.

  • For example, the array [3,2,5] (minimum value is 2) has a min-product of 2 (3+2+5) = 2 10 = 20.

Given an array of integers nums, return the maximum min-product of any non-empty subarray of nums. Since the answer may be large, return it modulo 109 + 7.

Note that the min-product should be maximized before performing the modulo operation. Testcases are generated such that the maximum min-product without modulo will fit in a 64-bit signed integer.

A subarray is a contiguous part of an array.

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[LeetCode] Interleaving String

97. Interleaving String

Given strings s1, s2, and s3, find whether s3 is formed by an interleaving of s1 and s2.

An interleaving of two strings s and t is a configuration where they are divided into non-empty substrings such that:

  • s = s1 + s2 + … + sn
  • t = t1 + t2 + … + tm
  • |n - m| <= 1
  • The interleaving is s1 + t1 + s2 + t2 + s3 + t3 + … or t1 + s1 + t2 + s2 + t3 + s3 + …

Note: a + b is the concatenation of strings a and b.

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[LeetCode] Largest Number After Mutating Substring

1946. Largest Number After Mutating Substring

You are given a string num, which represents a large integer. You are also given a 0-indexed integer array change of length 10 that maps each digit 0-9 to another digit. More formally, digit d maps to digit change[d].

You may choose to mutate a single substring of num. To mutate a substring, replace each digit num[i] with the digit it maps to in change (i.e. replace num[i] with change[num[i]]).

Return a string representing the largest possible integer after mutating (or choosing not to) a single substring of num.

A substring is a contiguous sequence of characters within the string.

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[LeetCode] Maximum Number of Points with Cost

1937. Maximum Number of Points with Cost

You are given an m x n integer matrix points (0-indexed). Starting with 0 points, you want to maximize the number of points you can get from the matrix.

To gain points, you must pick one cell in each row. Picking the cell at coordinates (r, c) will add points[r][c] to your score.

However, you will lose points if you pick a cell too far from the cell that you picked in the previous row. For every two adjacent rows r and r + 1 (where 0 <= r < m - 1), picking cells at coordinates (r, c1) and (r + 1, c2) will subtract abs(c1 - c2) from your score.

Return the maximum number of points you can achieve.

abs(x) is defined as:

  • x for x >= 0.
  • -x for x < 0.
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[LeetCode] Count Primes

204. Count Primes

Given an integer n, return the number of prime numbers that are strictly less than n.

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[LeetCode] Find All Possible Recipes from Given Supplies

2115. Find All Possible Recipes from Given Supplies

You have information about n different recipes. You are given a string array recipes and a 2D string array ingredients. The ith recipe has the name recipes[i], and you can create it if you have all the needed ingredients from ingredients[i]. Ingredients to a recipe may need to be created from other recipes, i.e., ingredients[i] may contain a string that is in recipes.

You are also given a string array supplies containing all the ingredients that you initially have, and you have an infinite supply of all of them.

Return a list of all the recipes that you can create. You may return the answer in any order.

Note that two recipes may contain each other in their ingredients.

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[LeetCode] Check if a Parentheses String Can Be Valid

2116. Check if a Parentheses String Can Be Valid

A parentheses string is a non-empty string consisting only of ‘(‘ and ‘)’. It is valid if any of the following conditions is true:

  • It is ().
  • It can be written as AB (A concatenated with B), where A and B are valid parentheses strings.
  • It can be written as (A), where A is a valid parentheses string.

You are given a parentheses string s and a string locked, both of length n. locked is a binary string consisting only of ‘0’s and ‘1’s. For each index i of locked,

  • If locked[i] is ‘1’, you cannot change s[i].
  • But if locked[i] is ‘0’, you can change s[i] to either ‘(‘ or ‘)’.

Return true if you can make s a valid parentheses string. Otherwise, return false.

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[LeetCode] Minimize the Difference Between Target and Chosen Elements

1981. Minimize the Difference Between Target and Chosen Elements

You are given an m x n integer matrix mat and an integer target.

Choose one integer from each row in the matrix such that the absolute difference between target and the sum of the chosen elements is minimized.

Return the minimum absolute difference.

The absolute difference between two numbers a and b is the absolute value of a - b.

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[LeetCode] Change Minimum Characters to Satisfy One of Three Conditions

1737. Change Minimum Characters to Satisfy One of Three Conditions

You are given two strings a and b that consist of lowercase letters. In one operation, you can change any character in a or b to any lowercase letter.

Your goal is to satisfy one of the following three conditions:

  • Every letter in a is strictly less than every letter in b in the alphabet.
  • Every letter in b is strictly less than every letter in a in the alphabet.
  • Both a and b consist of only one distinct letter.

Return the minimum number of operations needed to achieve your goal.

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[LeetCode] Sentence Similarity III

1813. Sentence Similarity III

A sentence is a list of words that are separated by a single space with no leading or trailing spaces. For example, “Hello World”, “HELLO”, “hello world hello world” are all sentences. Words consist of only uppercase and lowercase English letters.

Two sentences sentence1 and sentence2 are similar if it is possible to insert an arbitrary sentence (possibly empty) inside one of these sentences such that the two sentences become equal. For example, sentence1 = “Hello my name is Jane” and sentence2 = “Hello Jane” can be made equal by inserting “my name is” between “Hello” and “Jane” in sentence2.

Given two sentences sentence1 and sentence2, return true if sentence1 and sentence2 are similar. Otherwise, return false.

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