package javaArray;

import java.sql.Date;

public class A2 {

	public static void main(String[] args) {
		int a[] = new int[5];
		Date[] days = new Date[3];
		
		System.out.println(a[3]);
		System.out.println(days[2]);
		
		int[] data = new int[] {3, 9, 2, 8, 7, 0, 4, 6, 5, 1};

		showArray(data);
		
		bubbleSort(data);
		showArray(data);
		
		selectSort(data);
		showArray(data);
		
		insertSort(data);
		showArray(data);
		
	}

	/**
	 * showArray
	 * @param data
	 */
	public static void showArray(int[] data)
	{
		for (int i = 0; i < data.length; i++)
		{
			System.out.print(data[i] + "  ");
		}
		System.out.println();
	}
	
	/**
	 * bubbleSort
	 * @param a
	 */
	public static void bubbleSort(int[] a)
	{
		int len = a.length;
		for (int i = 0; i < len - 1; i++)
		{
			for (int j = 0; j < len - i - 1; j++)
			{
				if (a[j] > a[j + 1])
				{
					a[j] ^= a[j + 1];
					a[j + 1] ^= a[j];
					a[j] ^= a[j + 1]; 
				}
			}
		}
	}

	/**
	 * selectSort
	 * @param a
	 */
	public static void selectSort(int[] a)
	{
		int len = a.length;
		for (int i = 0; i < len - 1; i++)
		{
			int tmp = i;
			for (int j = i + 1; j < len; j++)
			{
				if (a[tmp] < a[j])
				{
					tmp = j;
				}
			}
			if (tmp != i)
			{
				a[tmp] ^= a[i];
				a[i] ^= a[tmp];
				a[tmp] ^= a[i]; 				
			}
		}
	}
	
	/**
	 * insertSort
	 * @param a
	 */
	public static void insertSort(int[] a)
	{
		for (int i = 1; i < a.length; i++)
		{
			for (int j = i; j > 0; j--)
			{
				if (a[j] < a[j - 1])
				{
					a[j] ^= a[j - 1];
					a[j - 1] ^= a[j];
					a[j] ^= a[j - 1]; 				
				}
				else {
					break;
				}
			}
		}
	}
	
	
	
}

<pre name="code" class="java">	/**
	 * 
	 * @param a
	 * @param num
	 * @return
	 */
	public static int binarySearch(int[] a, int num)
	{
		int start = 0;
		int end = a.length - 1;
		int mid = (start + end) / 2;
		
		if (a.length == 0)
			return -2;
		
		while(start <= end)
		{
			if (a[mid] > num)
			{
				end = mid - 1;
				mid = (start - end) / 2;
			}
			else if (a[mid] < num)
			{
				start = mid + 1;
				mid = (start + end) / 2;
			}
			else {
				return mid;
			}
		}
		
		
		return -1;
	}