import sys
input = sys.stdin.readline
enum = enumerate
inf = 1001001001
MOD = 10**9 + 7

import collections as cl
import itertools as it
import random
from bisect import bisect_right as bs_r

def linput(ty=int, cvt=list):
	return cvt(map(ty,input().split()))

def vinput(rep=1, ty=int, cvt=list):
	return cvt(ty(input().rstrip()) for _ in range(rep))

def drint(*v, **d):
	if 1: print(*v, **d, file=sys.stderr)

def dist(x1,y1,x2,y2):
	return abs(x1-x2)+abs(y1-y2)

#vD = [chr(ord("a")+i) for i in range(26)]
#vD = [(-1,0),(0,-1),(0,1),(1,0)]
vT = "0123456789"

def bye(res):
	sT = "No Yes".split()
	print(sT[res])
	#exit(0)

def csum(v):
	vr = [0,]
	s = 0
	for a in v:
		s = (s+a)
		vr.append(s)
	return vr

def main():
	N, = linput()
	
	res = 0
	res = (N-1)*(N-1)

	#for vr in mR:
	#	print(*vr, sep=" ")
	print(res)
	
	
if __name__ == "__main__":
	main()