摘要：
Given an array A of positive integers, call a (contiguous, not necessarily distinct) subarray of A good if the number of different integers in that su 阅读全文
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：
Given an array equations of strings that represent relationships between variables, each string equations[i] has length 4 and takes one of two differe 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