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 Kotlin (1.3.71) (judge verdict: Accepted)

import java.util.Scanner;

fun main (args : Array<String>) {
  val input = Scanner(System.`in`)
    
  while (input.hasNext()) {
    val A = input.nextLong()
    val B = input.next()
    val ans = ((A * ((B[0] - '0') * 100)) + (A * B.substring(2).toLong())) / 100
    
    println(ans)
  }
}