import math
from decimal import Decimal
a, b = input().split()
a = Decimal(a)
b = Decimal(b)
print(math.floor(a * b))

75b5ab87b84adcd7b55eb6439e9c8376d301e818
<mask token>

<mask token>
print(math.floor(a * b))

<mask token>
a, b = input().split()
a = Decimal(a)
b = Decimal(b)
print(math.floor(a * b))

import math
from decimal import Decimal
a, b = input().split()
a = Decimal(a)
b = Decimal(b)
print(math.floor(a * b))
