    import java.util.Scanner;
    
    public class Main {
    	public static void main(String[] args){
    		Scanner scan = new Scanner(System.in);
    		long a = scan.nextLong();
    		double b = scan.nextDouble();
    		long c = (long) (a*b);
    		System.out.println(c);
    	}
    }
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz