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.
The only line of the input contains one integer *n* (7 ≤ *n* ≤ 777) — the number of potential employees that sent resumes.
none
7
29
8
92
9
246
10
582
321
66715035255088
624
7147161340917624
666
11292070960994226
700
16017044425409540
776
33019955679376860
777
33319741730082870
from math import factorial

n = int(input())

factorial(n) / factorial(n)

r1 = factorial(n) // (factorial(7)*factorial(n-7))
r2 = factorial(n) // (factorial(6)*factorial(n-6))
r3 = factorial(n) // (factorial(5)*factorial(n-5))

print(r1 + r2 + r3)


