import java.util.Arrays;
import java.util.Random;

public class ReverseTest {

  public static Random rand = new Random();

  /**
   * requires: - 'array' is not null
   * ensures:  - for each element at position 'i' in 'array', it has the same
   *             value as 'array[array.length - 1 - i]' in the pre-state.
   **/
  public static void reverse(int[] array) {
    for (int i = 0; i < array.length / 2; i++) {
      array[i] = array[array.length - i - 1];
      array[array.length - i - 1] = array[i];
    }
  }

  public static int[] generate(int length) {
    // TODO generate array of specified length.
    return null;
  }

  public static boolean test(int[] array) {
    try {
      // TODO check that reversing works
      // What properties make sense? Note that the reverse works in-place.
      return false;
    } catch (Exception e) {
      e.printStackTrace();
      return false;
    }
  }

  public static void main(String[] arg) {
    for (int i = 0; i < 10000; i++) {
      int[] array = generate(rand.nextInt(30));
      if (!test(array)) {
        System.out.println("Failed: " + Arrays.toString(array));
        System.exit(0);
      }
    }
    System.out.println("Done.");
  }

}