from decimal import Decimal, getcontext

# Set a high precision to handle all possible cases accurately.
getcontext().prec = 1000

N = int(input())

# Calculate (3/4) as a Decimal to ensure precision.
d = Decimal(3) / Decimal(4)
power = d ** N
result = Decimal(4) * power

# Round the result to 8 decimal places.
rounded_result = result.quantize(Decimal('1.00000000'))

# Format the output to ensure exactly 8 decimal places.
print("{0:.8f}".format(rounded_result))