# LeetCode 119. Pascal’s Triangle II

Description https://leetcode.com/problems/pascals-triangle-ii/ Given an integer rowIndex, return the rowIndexth (0-indexed) row of the Pascal’s triangle. In Pascal’s triangle, each number is the sum of the…

# LeetCode 1758. Minimum Changes To Make Alternating Binary String

Description https://leetcode.com/problems/minimum-changes-to-make-alternating-binary-string/ You are given a string s consisting only of the characters ‘0’ and ‘1’. In one operation, you can change any ‘0’ to ‘1’ or vice versa.…

# LeetCode 404. Sum of Left Leaves

Description https://leetcode.com/problems/sum-of-left-leaves/ Given the root of a binary tree, return the sum of all left leaves. Example 1: Input: root = [3,9,20,null,null,15,7]…

# LeetCode 1790. Check if One String Swap Can Make Strings Equal

Description https://leetcode.com/problems/check-if-one-string-swap-can-make-strings-equal/ You are given two strings s1 and s2 of equal length. A string swap is an operation where you choose two indices in a…

# LeetCode 1694. Reformat Phone Number

Description https://leetcode.com/problems/reformat-phone-number/ You are given a phone number as a string number. number consists of digits, spaces ‘ ‘, and/or dashes ‘-‘. You would like…

# LeetCode 1323. Maximum 69 Number

Description https://leetcode.com/problems/maximum-69-number/ Given a positive integer num consisting only of digits 6 and 9. Return the maximum number you can get by…

# LeetCode 1179. Reformat Department Table

Description https://leetcode.com/problems/reformat-department-table/ SQL Schema Table: Department +—————+———+ | Column Name | Type | +—————+———+ | id | int | | revenue…

# LeetCode 1844. Replace All Digits with Characters

Description https://leetcode.com/problems/replace-all-digits-with-characters/ You are given a 0-indexed string s that has lowercase English letters in its even indices and digits in its odd indices. There is a function shift(c,…

# LeetCode 1450. Number of Students Doing Homework at a Given Time

Description https://leetcode.com/problems/number-of-students-doing-homework-at-a-given-time/ Given two integer arrays startTime and endTime and given an integer queryTime. The ith student started doing their homework at the time startTime[i] and finished it at…

# LeetCode 1848. Minimum Distance to the Target Element

Description https://leetcode.com/problems/minimum-distance-to-the-target-element/ Given an integer array nums (0-indexed) and two integers target and start, find an index i such that nums[i] == target and abs(i – start) is minimized. Note that abs(x) is the absolute…