在路上的豆丁

摘要： For a non-negative integer X, the array-form of X is an array of its digits in left to right order. For example, if X = 1231, then the array form is [ 阅读全文

摘要： The Fibonacci numbers, commonly denoted F(n) form a sequence, called the Fibonacci sequence, such that each number is the sum of the two preceding one 阅读全文

摘要： Given a non-negative integer, you could swap two digits at most once to get the maximum valued number. Return the maximum valued number you could get. 阅读全文