LeetCode Q 231 - Power of TwoGiven an integer, write a function to determine if it is a power of two. Example 1: Input:

LeetCode Q 227 - Basic Calculator IIImplement a basic calculator to evaluate a simple expression string. The expression

LeetCode Q 224 - Basic CalculatorImplement a basic calculator to evaluate a simple expression string. The expression str

LeetCode Q 171 - Excel Sheet Column NumberGiven a column title as appear in an Excel sheet, return its corresponding col

LeetCode Q 168 - Excel Sheet Column TitleGiven a positive integer, return its corresponding column title as appear in an

LeetCode Q 172 - Factorial Trailing ZeroesGiven an integer n, return the number of trailing zeroes in n!. Example 1: Inp