摘要： #include // To read from the standard input, we write std::cin. These names use the // scope operatro(::), which says that the compiler should look in 阅读全文

摘要： The Simple Arithmetic Sequences Let's say we have the simplest of arithmetic sequences. $\{1, 2, 3, \cdot\cdot\cdot, n\}$ And what I want to think abo 阅读全文