Implement pow(x, n), which calculates x raised to the power n (xn).
The n-queens puzzle is the problem of placing n queens on an n_×_n chessboard such that no two queens attack each other.
Roman numerals are represented by seven different symbols: I, V, X, L, C, D and M.
Convert a non-negative integer to its english words representation. Given input is guaranteed to be less than 231 - 1.
Determine whether an integer is a palindrome. An integer is a palindrome when it reads the same backward as forward.
Given a list of non negative integers, arrange them such that they form the largest number.
The count-and-say sequence is the sequence of integers with the first five terms as following:
Given a positive integer, return its corresponding column title as appear in an Excel sheet.
Median is the middle value in an ordered integer list. If the size of the list is even, there is no middle value. So the median is the mean of the two middle va...
