Problem:
Score : 300 points

Problem Statement

Compute A \times B, truncate its fractional part, and print the result as an integer.

Constraints

0 \leq A \leq 10^{15}

0 \leq B < 10

A is an integer.

B is a number with two digits after the decimal point.

Input

Input is given from Standard Input in the following format:

A B

Output

Print the answer as an integer.

Sample Input 1

198 1.10

Sample Output 1

217

We have 198 \times 1.10 = 217.8. After truncating the fractional part, we have the answer: 217.

Sample Input 2

1 0.01

Sample Output 2

0

Sample Input 3

1000000000000000 9.99

Sample Output 3

9990000000000000

Solution in Fortran (GNU Fortran 9.2.1) (judge verdict: Accepted)

      PROGRAM piyo
      IMPLICIT NONE
      INTEGER,PARAMETER :: prec = 16
      real(prec) :: b
      integer(prec) :: aa,bb
      
      read*,aa,b
      

      bb = nint( b*100_prec )
      print*,aa*bb/100_prec
      
      
      stop
      !debugg
      
      !BADBADBADBADBADBADBADBADBADBADBADBAD!
      
      END PROGRAM