import java.util.Random;

/**
 * Class TestMergeSort.
 *
 * @author Philipp Bolliger <br>
 * Informatik II - FS2009 <br>
 * Uebungsserie 10
 */
public class TestMergeSort {

	public static void main(String[] args) {

		//create a test array of Comparable items
		Integer [] testArray;
		int numElements[] = {1000, 5000, 25000, 50000, 100000, 500000, 1000000};
		float avgExecTime[] = new float[numElements.length];

		for(int j=0; j <numElements.length; j++) {
			long totalTime = 0;

			testArray = createTestArray(numElements[j]);

			MergeSort.mergeSort(testArray);

			//store the current result
			avgExecTime[j] = totalTime;

			//print the current result
			System.out.println("Sorting " + numElements[j] + " elements takes " + totalTime + " ms");
		}
	}

	/**
	 * Creates and returns an array of n random Integers. <br>
	 *
	 * @param n number of elements in the array to be created
	 * @return an array of n random elements
	 */
	public static Integer[] createTestArray( int n ) {
		Integer [] a = new Integer[n];
		Random rnd = new Random();
		for ( int i = 0; i < n; i++ ) {
			a[ i ] = new Integer(rnd.nextInt( 1001 ));
		}
		return a;
	}

	/**
	 * Prints an array of Comparable items.
	 * @param a the array to print.
	 */
	public static void print(Comparable [] a) {
		for ( int i = 0; i < a.length; i++ ) {
			System.out.print(a[i].toString() + " ");
		}
		System.out.println();
	}
}