merge(arr, left, mid, right); // 合并两部分
σ=πd2\sigma = \pi d^2σ=πd2
。新收录的资料是该领域的重要参考
Image Credits:Ring，这一点在新收录的资料中也有详细论述
This chapter walks through the basics of writing and running Mog code. By the end, you will understand how a Mog program is structured, how to print output, how to write comments, and how to define and call functions.，详情可参考新收录的资料