public class Test
{
    public static void swap(int x, int y)
    {
        int tmp = x;
        x = y;
        y = tmp;
        
        System.out.println("x = " + x);
        System.out.println("y = " + y);
    }

    public static void printArray(int[] X)
    {
        for (int i = 0; i < X.length; i++)
        {
            System.out.println("X[" + i + "] = " + X[i]);            
        }
    }

    public static void swap(int[] X, int pos1, int pos2)
    {
        int tmp = X[pos1];
        X[pos1] = X[pos2];
        X[pos2] = tmp;
    }
    
    public static int getMaxIndex(int[] X)
    {
        int largest = 0;
        for (int i = 0; i < X.length; i++)
        {
            if (X[i] > X[largest])
            {
                largest = i;
            }
        }
        return largest;
    }
    

    public static int search(int X[], int key)
    {
        for (int i = 0; i < X.length; i++)
        {
            if (X[i] == key)
                return i;
        }
        return -1;
    }
    
    public static void main(String args[])
    {
        int[] A = new int[10];
        for (int i = 0; i < A.length; i++)
        {
            A[i] = 2 * (i + 1);
        }
        
        System.out.println(search(A, 10));
        swap(A, 0, A.length-1);
        System.out.println(search(A, 20));
        System.out.println(search(A, 1));
        
    }
}