from decimal import Decimal

import math 



A,B = input().split()

A = int(A)

B = Decimal(B)



print((int(math.floor(A*B))))
#有理数演算



from math import floor

from fractions import Fraction



a, b = input().split()

a = int(a)

b = Fraction(b)

print((floor(a * b)))
from decimal import Decimal
import math

A, B = input().split()
A = int(A)
B = Decimal(B)
print((int(math.floor(A * B))))

# 有理数演算
from math import floor
from fractions import Fraction

a, b = input().split()
a = int(a)
b = Fraction(b)
print((floor(a * b)))

-from decimal import Decimal -import math +# 有理数演算 +from math import floor +from fractions import Fraction -A, B = input().split() -A = int(A) -B = Decimal(B) -print((int(math.floor(A * B)))) +a, b = input().split() +a = int(a) +b = Fraction(b) +print((floor(a * b)))