摘要：
On a broken calculator that has a number showing on its display, we can perform two operations: Double: Multiply the number on the display by 2, or; D 阅读全文
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