Selection of Personnel

题意翻译

你所在的公司想要组建一个由5-7人构成的全新团队。于是高层发出了招聘信息，并有n人应聘。 公司的高层要求你告诉他们，在这n个人中任意挑选组成一个团队的方案数。 输入一行一个数字n（7<=n<=777）. 输出一行一个数字ans表示方案数，不需要取模。

题目描述

One company of IT City decided to create a group of innovative developments consisting from $ 5 $ to $ 7 $ people and hire new employees for it. After placing an advertisment the company received $ n $ resumes. Now the HR department has to evaluate each possible group composition and select one of them. Your task is to count the number of variants of group composition to evaluate.

输入输出格式

输入格式

The only line of the input contains one integer $ n $ ( $ 7<=n<=777 $ ) — the number of potential employees that sent resumes.

输出格式

Output one integer — the number of different variants of group composition.

输入输出样例

输入样例 #1

7

输出样例 #1

29