import sys
input = sys.stdin.readline

N=int(input())

if N%2==1:
    print(0)
    exit()

x=N//2
DP=[0]*(x+1)
DP[0]=1

ANS=0

for i in range(N):
    #print(DP,ANS)
    NDP=[0]*(x+1)

    for j in range(x+1):
        if j+1<=x and j+1-(N-i-1)<=0:
            NDP[j+1]+=DP[j]
        if j-1>=0:
            NDP[j-1]+=DP[j]
            ANS+=(j-1)*DP[j]

    DP=NDP

print(ANS)