Blackone

// VitosFamily.java
// Jeffrey Cartagena

import java.io.*;
import java.util.Scanner;


public class VitosFamily {

    public static void main(String[] args) throws IOException{
        try{
            Scanner inFile = new Scanner(new FileReader("data.in"));
            PrintWriter outFile = new PrintWriter(new FileWriter("data.out"));

            int qty = inFile.nextInt();
            int sentinel = 0;

            while(sentinel < qty)
            {
                int relatives = inFile.nextInt();

                int[] streets = new int[relatives];

                for(int i=0; i < relatives; i++)
                    streets[i] = inFile.nextInt();

                int result = 0;

                for(int i=relatives-1; i>0; i--)
                    result += (streets[i] - streets[i-1]);

                outFile.println(result);

                sentinel++;

            }

            System.out.println("Finishing the program");
            System.in.read();

            inFile.close();
            outFile.close();
        }

        catch(IOException ex)
        {
            System.out.println("There is no input file");
            System.in.read();
        }
    }
}