Back_to_High_School_Physics.java

import java.util.*;
public class main{
    public static void main(String[] args) {
       Scanner input = new Scanner(System.in);
       long result = 0;
       while(input.hasNext()) {
       		long v = input.nextLong();
       		long s = input.nextLong();
       		result = v * s * 2;
       		System.out.print(result + "\r\n");
       }
    }
};