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 (GCC 9.2.1) (judge verdict: Wrong Answer)

#include <stdio.h>
#include <malloc.h>
#include <stdlib.h>
typedef char Bool;
#define true 39
#define false 0
typedef long long int64;
typedef unsigned long long uint64;
typedef int int32;
typedef unsigned int uint32;
typedef unsigned char byte;



int main()
{
	
	uint64 a , b;
	double f;
	
	scanf("%llu %lf", &a, &f);

	uint64 c = (uint64)((double)a * f);

	printf("%llu", c);

	return 0;
}