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 Go (1.14.1) (judge verdict: Wrong Answer)

package main

import (
	"bufio"
	"fmt"
	"math"
	"os"
	"strconv"
	"strings"
)

// go run ./main.go < in

func main() {
	sc := bufio.NewScanner(os.Stdin)
	for i := 0; i <= 0; i++ {
		sc.Scan()
		inputs := strings.Split(sc.Text(), " ")
		a, _ := strconv.ParseFloat(inputs[0], 64)
		b, _ := strconv.ParseFloat(inputs[1], 64)

		fmt.Println(int(math.Floor(a * b)))

	}

}