from decimal import Decimal

p_str = input().strip()
p = Decimal(p_str)
denominator = Decimal(1) - p

if denominator == 0:
    print(0)
else:
    e = p / denominator
    e_str = format(e, 'f')  # Convert to non-exponential string
    if '.' in e_str:
        e_str = e_str.rstrip('0').rstrip('.')
    print(e_str)