from decimal import Decimal



a,b = input().split()

b = b.replace(".","")

c = int(a)*int(b)//100



print(c)

from decimal import Decimal



a,b = list(map(float,input().split()))

b = round(b*100)

c = int(a)*int(b)//100



print(c)

from decimal import Decimal

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

from decimal import Decimal

a, b = list(map(float, input().split()))
b = round(b * 100)
c = int(a) * int(b) // 100
print(c)

-a, b = input().split() -b = b.replace(".", "") +a, b = list(map(float, input().split())) +b = round(b * 100)