leetcode

Given a fixed length array arr of integers, duplicate each occurrence of zero, shifting the remaining elements to the right. Note that elem…

In MATLAB, there is a very useful function called 'reshape', which can reshape a matrix into a new one with different size but keep its ori…

Given two arrays arr1 and arr2, the elements of arr2 are distinct, and all elements in arr2 are also in arr1. Sort the elements of arr1 suc…

A matrix is Toeplitz if every diagonal from top-left to bottom-right has the same element. Now given an M x N matrix, return True if and on…

Given a matrix A, return the transpose of A. The transpose of a matrix is the matrix flipped over it's main diagonal, switching the row and…

Given an array A of strings made only from lowercase letters, return a list of all characters that show up in all strings within the list (…

The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the two pr…

Given an array A of non-negative integers, half of the integers in A are odd, and half of the integers are even. Sort the array so that whe…

Given a binary matrix A, we want to flip the image horizontally, then invert it, and return the resulting image. To flip an image horizonta…

Given an array of integers A sorted in non-decreasing order, return an array of the squares of each number, also in sorted non-decreasing o…

Students are asked to stand in non-decreasing order of heights for an annual photo. Return the minimum number of students not standing in t…