from fractions import Fraction



A,B = input().split()

#A = int(A)

#B = float(B)



from decimal import *



a = Decimal(A)

b = Decimal(B)

getcontext().prec = 28

ans = a * b

print((int(ans)))

import sys

readline = sys.stdin.readline



A,B = readline().split()

A = int(A)

B = int(float(B) * 100 + 0.5)



print((A * B // 100))
from fractions import Fraction

A, B = input().split()
# A = int(A)
# B = float(B)
from decimal import *

a = Decimal(A)
b = Decimal(B)
getcontext().prec = 28
ans = a * b
print((int(ans)))

import sys

readline = sys.stdin.readline
A, B = readline().split()
A = int(A)
B = int(float(B) * 100 + 0.5)
print((A * B // 100))

-from fractions import Fraction +import sys -A, B = input().split() -# A = int(A) -# B = float(B) -from decimal import * - -a = Decimal(A) -b = Decimal(B) -getcontext().prec = 28 -ans = a * b -print((int(ans))) +readline = sys.stdin.readline +A, B = readline().split() +A = int(A) +B = int(float(B) * 100 + 0.5) +print((A * B // 100))