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Leetcode 746: Min Cost Climbing Stairs

You are climbing a staircase with a cost associated with each step. You can either start at the first or second step. At each step, you can either move one step or skip one step. Find the minimum cost to reach the top of the staircase.

Aug 24, 2024 - 4 min read

Leetcode 762: Prime Number of Set Bits in Binary Representation

Given two integers left and right, return the count of numbers in the inclusive range [left, right] having a prime number of set bits in their binary representation. The number of set bits in a number is the count of 1’s when the number is represented in binary. A prime number is a number greater than 1 that is divisible only by 1 and itself.

Aug 22, 2024 - 5 min read

Leetcode 824: Goat Latin

You are given a sentence with words separated by spaces. Each word consists of only lowercase and uppercase letters. Your task is to convert the sentence into a new language called ‘Goat Latin’ by following the rules below:

  1. If a word begins with a vowel (‘a’, ’e’, ‘i’, ‘o’, or ‘u’), append ‘ma’ to the end of the word.
  2. If a word begins with a consonant, remove the first letter, move it to the end, and add ‘ma’.
  3. Add one letter ‘a’ to the end of each word depending on its position in the sentence (1st word gets ‘a’, 2nd gets ‘aa’, 3rd gets ‘aaa’, etc.).

Return the final sentence in Goat Latin.

Aug 16, 2024 - 6 min read

Leetcode 836: Rectangle Overlap

You are given two axis-aligned rectangles represented by two lists, rec1 and rec2. Each list contains four integers: [x1, y1, x2, y2], where (x1, y1) represents the bottom-left corner and (x2, y2) represents the top-right corner of the rectangle. You need to determine if the two rectangles overlap. Two rectangles overlap if their intersection area is positive. Rectangles that only touch at the edges or corners do not count as overlapping.

Aug 15, 2024 - 5 min read

Leetcode 844: Backspace String Compare

You are given an integer array arr. A mountain array is an array where the elements first strictly increase to a peak and then strictly decrease after that peak. Your task is to find the length of the longest mountain subarray in the given array. If no such subarray exists, return 0.

Aug 14, 2024 - 6 min read

Leetcode 859: Buddy Strings

You are given two strings, s and goal, consisting of lowercase letters. Your task is to determine whether you can swap exactly two characters in s so that the resulting string matches goal. If this is possible, return true, otherwise return false. The swap is defined as selecting two different indices i and j, and swapping the characters at those positions in s.

Aug 13, 2024 - 7 min read