Coding Problems

Given a string, return the string reversed.

Calculate the factorial of a given non-negative integer.

Write a program that takes two numbers as input and returns their sum.

Given the root of a binary tree, return the inorder traversal of its nodes' values. Inorder traversal visits nodes in …

Given two sorted arrays nums1 and nums2 of size m and n respectively, return the median of the two sorted …

Given a string s, find the length of the longest substring without repeating characters. A substring is a contiguous non-empty …

Given an integer x, return true if x is a palindrome, and false otherwise. An integer is a palindrome when …

Calculate minimum flips (0→1 or 1→0) to make binary string alternating

Find maximum number of substrings that meet criteria and don't overlap

Count strings of length n between s1 and s2 without evil as substring

Add characters in front to make shortest palindrome

Split text into maximum parts where parts read same forwards and backwards

Calculate minimum insertions needed to balance parentheses

Sum counts of unique characters in all substrings

Find all unique index pairs (i,j) where words[i]+words[j] is palindrome

Determine if str1 can be transformed into str2 with character mappings

Calculate operations needed to make string sorted (mod 10^9+7)

Find the longest substring that occurs at least twice in a string

Find smallest range that includes at least one number from each of k lists

Find all starting indices of substrings that are concatenation of each word