ans1 = 0
ans2 = 0
for i in range(1, 10) :
    for j  in range(1, 10) :
        if i + j < 10 :
            ans1 += 1
for i in range(0, 10) :
    for j  in range(0, 10) :
        if i + j < 10 :
            ans2 += 1

n = int(input())

for i in range (1, n) :
    ans1 *= ans2

print(ans1)

How this work?