CL Fei1021. Remove Outermost ParenthesesA valid parentheses string is either empty "", "(" + A + ")", or A + B, where A and B are valid parentheses strings, and + represents…2 min read·Aug 6, 2023----
CL Fei853. Car FleetThere are n cars going to the same destination along a one-lane road. The destination is target miles away.3 min read·Jul 8, 2022----
CL Fei56. Merge IntervalsGiven an array of intervals where intervals[i] = [starti, endi], merge all overlapping intervals, and return an array of the…2 min read·Jun 4, 2022----
CL Fei442. Find All Duplicates in an ArrayGiven an integer array nums of length n where all the integers of nums are in the range [1, n] and each integer appears once or twice…2 min read·Jun 2, 2022----
CL Fei189. Rotate ArrayGiven an array, rotate the array to the right by k steps, where k is non-negative.2 min read·Jun 1, 2022----
CL Fei49. Group AnagramsGiven an array of strings strs, group the anagrams together. You can return the answer in any order.1 min read·May 31, 2022----
CL Fei67. Add BinaryGiven two binary strings a and b, return their sum as a binary string.2 min read·May 29, 2022----
CL Fei136. Single NumberGiven a non-empty array of integers nums, every element appears twice except for one. Find that single one.1 min read·May 24, 2022----
CL Fei204. Count PrimesGiven an integer n, return the number of prime numbers that are strictly less than n.2 min read·May 22, 2022----
CL Fei836. Rectangle OverlapAn axis-aligned rectangle is represented as a list [x1, y1, x2, y2], where (x1, y1) is the coordinate of its bottom-left corner, and (x2…2 min read·May 20, 2022----