摘要： Problem Statement There is an image with a height of H pixels and a width of W pixels. Each of the pixels is represented by either . or *. The charact 阅读全文

摘要： Problem Statement There are N boxes arranged in a row. Initially, the i-th box from the left contains ai candies. Snuke can perform the following oper 阅读全文

摘要： Problem Statement You are given nonnegative integers a and b (a≤b), and a positive integer x. Among the integers between a and b, inclusive, how many 阅读全文