汉诺塔问题&数组Dominato&non-negative integer

1 汉诺塔运行结果：

引用

input number: 5
Disk 1 From A To C
Disk 2 From A TO B
Disk 1 From C To B
Disk 3 From A TO C
Disk 1 From B To A
Disk 2 From B TO C
Disk 1 From A To C
Disk 4 From A TO B
Disk 1 From C To B
Disk 2 From C TO A
Disk 1 From B To A
Disk 3 From C TO B
Disk 1 From A To C
Disk 2 From A TO B
Disk 1 From C To B
Disk 5 From A TO C
Disk 1 From B To A
Disk 2 From B TO C
Disk 1 From A To C
Disk 3 From B TO A
Disk 1 From C To B
Disk 2 From C TO A
Disk 1 From B To A
Disk 4 From B TO C
Disk 1 From A To C
Disk 2 From A TO B
Disk 1 From C To B
Disk 3 From A TO C
Disk 1 From B To A
Disk 2 From B TO C
Disk 1 From A To C

import java.io.*;

public class Hanoi {
	public static void main(String args[]) throws IOException {
		int n;
		BufferedReader buf;
		buf = new BufferedReader(new InputStreamReader(System.in));
		System.out.print("input number: ");
		n = Integer.parseInt(buf.readLine());
		Hanoi hanoi = new Hanoi();
		hanoi.move(n, 'A', 'B', 'C');
	}

	public void move(int n, char a, char b, char c) {
		if (n == 1)
			System.out.println("Disk " + n + " From " + a + " To " + c);
		else {
			move(n - 1, a, c, b);
			System.out.println("Disk " + n + " From " + a + " TO " + c);
			move(n - 1, b, a, c);
		}
	}
}

2 Array Dominator

import java.util.Hashtable;

import junit.framework.TestCase;

public class Dominator extends TestCase {
	public static int dominator(int[] a) {
		int result = -1;
		int length = a.length;

		Hashtable<Integer, Integer> countTable = new Hashtable<Integer, Integer>();

		for (int i = 0; i < length; i++) {
			if (countTable.containsKey(a[i])) {
				countTable.put(a[i], countTable.get(a[i]) + 1);
				if (countTable.get(a[i]) >= length / 2) {
					return i;
				}
			} else {
				countTable.put(a[i], 0);
			}
		}
		return result;
	}

	public void testDominator() {
		int[] array = { 1, 2, 3, 3, 3, 3, 3 };
		assertEquals(dominator(array), 5);
	}

}

public class HeavyNumberTest {
	static int count = 0;

	public static void main(String a[]) {
		// should be 5
		System.out.println(heavy(8675, 8689));
	}

	static int heavy(int a, int b) {
		int range = 0;

		if (a == 0 || b == 0)
			return 0;

		if (a > b)
			range = a - b;
		else
			range = b - a;

		for (int j = 0; j <= range; j++) {
			double avg = 0.0;
			int sum = 0;
			int n = 0;

			int currentNumber = a;
			while (currentNumber > 0) {
				sum += currentNumber % 10;
				currentNumber = currentNumber / 10;
				n++;
			}

			avg = ((double) sum) / ((double) n);
			if (avg > 7)
				count++;

			System.out.println(" " + avg + " \t " + count);

			a++;
		}

		return count;
	}
}