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 Rust (1.42.0) (judge verdict: Wrong Answer)

use std::io;

fn main() {
    let mut line = String::new();
    io::stdin().read_line(&mut line).expect("Failed to read line");
    let vec : Vec<&str> = line.split_whitespace().collect();
    
    let f1 : f64 = vec[0].parse().unwrap_or(0.0);
    let f2 : f64 = vec[1].parse().unwrap_or(0.0);

    let f_mul = f1 * f2;

    let n_mul : i64 = f_mul as i64;

    println!("{}", n_mul);
}