Problem Statement

Compute $A \times B,$ truncate its fractional part, and print the result as an integer.

Input

Input is given from Standard Input in the following format:
A B

Output

Print the answer 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.

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

见题面 Input 部分

见题面 Output 部分