冒泡排序和二分查找

/**

*

*/

package com.test.sort;

/**

* @author Administrator

*

*/

/**

*冒泡排序

*

*/

public class Bubbling

{

public static int[] Bubbling(int[] arr)

{

//int[] arr = {12,45,11,22,2,5,27,3,99,0};

for(int i = 0;i<arr.length;i++)

{

for(int j=0;j<arr.length-i-1;j++)

{

int temp;

if(arr[j]>arr[j+1])

{

temp = arr[j+1];

arr[j+1] = arr[j];

arr[j] = temp;

}

}

}

return arr;

}

}

--------------------------------------------------------------分隔符----------------------------------------------------------

二分查找以中间的数字大小儿子比较标准，假设是从小到大，中间数字大于所求数字，那肯定在左边，相同的方法定位左边字表的中间值在比较，相反则亦然

/**

*

*/

package com.test.sort;

/**

* @author Administrator

*二分查找

*/

public class BinarySearch

{

public static int binarySearch(int[] array, int value)

{

int low = 0;

int high = array.length-1;

int middle = 0;

while(low <= high)

{

middle = (low+high)/2;

if(array[middle] == value)

{

return middle;

}

if(value < array[middle])

{

high = middle - 1;

}

if(value > array[middle])

{

low = middle + 1;

}

}

return -1;

}

//递归

public static int binarySearch1(int[] array, int value,int low,int right)

{

int center = (low+right)/2;

if(array[center] == value)

{

System.out.println("找到了");

return center;

}

if(array[center] > value)

{

return binarySearch1(array,value,low,right -1);

}

if(array[center] < value)

{

return binarySearch1(array,value,center+1,right);

}

return -1;

}

public static void main(String[] args)

{

int[] array = {7,3,9,5,6,8,1};

int[] array1 = Bubbling.Bubbling(array);

//1356789

int index = binarySearch(array1,5);

System.out.println("所在的位置:"+index);

}

}