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 C# (Mono-csc 3.5.0) (judge verdict: Wrong Answer)

using System;
					
public class Program
{
	public static void Main()
	{
		//ulong N = ulong.Parse(Console.ReadLine());
		string[] str = Console.ReadLine().Split(' ');
		//int[] arr = new int[1000000];
		ulong A = ulong.Parse(str[0]);
		double B = double.Parse(str[1]);
		double result = A * B;
		
		Console.WriteLine(Math.Floor(result));
		
	}
}
 
public class Sol
{
	public double Solve(ulong A, ulong B, ulong x)
	{
		double ans;
		double tmp1 = (A*x)/B;
		double tmp2 = x/B;
		
		tmp1 = Math.Truncate(tmp1);
		tmp2 = Math.Truncate(tmp2);
		
		ans = tmp1 - (A*tmp2);
		
		return ans;
	}
}