在廖老师的上一讲《公式求和》之后，就是本讲《分组求和》的内容。分组求和是指把数列中的某些数通过整理，变为有规律的一组一组的数，从而快速简便地求出结果。分组求和，重在分组这一步，通过分组后，应该有利于下一步的简便计算。

推荐阅读：
How to Print Immutable Linked List in Reverse using Recursion or　 The Most Useful Tools for Reverse Phone Lookup　 How to Solve the WIFI (Wireless Networks) Intermittency Issues?　 How to Reverse a Linked List in Javascript?　 Bash Function to Check if a Kubernetes Pod Name is Valid　 VBScript Function to Convert an Integer to Binary String Represe　 Find Maximum Connected Colors (Values) in a 2D Grid using DFS or　 Algorithms to Shift a 2D Grid/Matrix In-Place　 How Martha Stewart Became One Of The Best Bloggers On The Web　 Social Media and Dating Apps: How They’re Changing Love