from decimal import *

a,b = input().split()



print((int(Decimal(a)*Decimal(b))))

a,b = input().split()



a = int(a)

b = int(b.replace('.',''))



print((a*b//100))

from decimal import *

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

a, b = input().split()
a = int(a)
b = int(b.replace(".", ""))
print((a * b // 100))

-from decimal import * - -print((int(Decimal(a) * Decimal(b)))) +a = int(a) +b = int(b.replace(".", "")) +print((a * b // 100))