排序的基本算法

一、交换排序

 //冒泡排序
static void sort_bubble(int[] a) { 
        int temp=0;
            for(int i=0;i<a.Length-1;i++){
             for(int j=i+1;j<a.Length;j++){
                if(a[i]>a[j]){
                    temp = a[i];
                    a[i] = a[j];
                    a[j] = temp;
                }
             }
            }
        }

 

//快速排序
   static int sourtUnit(int[] array, int low, int hight)
        {
            int key = array[low];
            while (low < hight)
            {
                while (low < hight && array[hight] > key)
                    hight--;
                array[low] = array[hight];

                while (low < hight && array[low] < key)
                    low++;
                array[hight] = array[low];
            }

            array[low] = key;
            return low;
        }
        static void sort(int[] array, int low, int hight)
        {
            if (low < hight)
            {
                //print(array);
                int index = sourtUnit(array, low, hight);
                sort(array, low, index - 1);
                sort(array, index + 1, hight);
            }
        }

 二、选择排序

  //选择排序
        static void sort_choice(int[] a) {
            int index = 0,temp=0;
            for (int i = 0; i < a.Length - 1; i++) {
                index = i;
                for (int j = i + 1; j < a.Length; j++)
                {
                    if (a[index] > a[j]) index = j;
                }
                if (index != i)
                {
                    temp = a[i];
                    a[i] = a[index];
                    a[index] = temp;
                }
               // print(a);
            }
        }

 

       //堆排序
        static void InitHeap(int[] a, int index,int length) {

            int left = 2 * index + 1;
            int right = 2 * index + 2;
            int max=index;
            if (index < length / 2)
            {
                if (left < length && a[max] < a[left])
                    max = left;
                if (right < length && a[max] < a[right])
                    max = right;
                if (max != index) {
                    int temp = a[index];
                    a[index] = a[max];
                    a[max] = temp;
                    InitHeap(a, max,length);
                }
               
            }

        }
//
         int[] c = getArray(100);
            print(c);
          
            for (int i = c.Length / 2 - 1; i >= 0; i--) {
                InitHeap(c, i,c.Length);
            }
            //然后倒序交换
            for (int i = c.Length - 1; i >= 0; i--)
            {

                int temp = c[0];
                c[0] = c[i];
                c[i] = temp;

                InitHeap(c, 0, i);
            }

           
            print(c);

 三、插入排序

 //直接插入排序
        static void sort_insert(int[] a) {
            int index = 0, temp = 0;
            for (int i = 1; i < a.Length; i++) {
                index = i;
                temp = a[i];
                while (index > 0 && a[index - 1] > temp) {
                    a[index] = a[index - 1];
                    index--;
                }
                a[index] = temp;
            }
        }

 

 //希尔排序
        static void sort_shell_insert(int[] a)
        {
            int length = a.Length;
            int interval = length / 2;

            while (interval != 0)
            {

                for (int i = interval; i < length; i++)
                {
                    int t = a[i];
                    int j = i - interval;
                    while (j >= 0 && t < a[j])
                    {
                        a[j + interval] = a[j];
                        j = j - interval;
                    }

                    a[j + interval] = t;
                }
                interval /= 2;
            }
        }  

 四、基数排序

public static void baseSort(int[] a,int d){
		//创建一个二维数组
		int [][]temp=new int[10][a.length];
		int[] length=new int[a.length];
		//循环次数
		int div=1;//除数
		int m=0;//控制循环次数
		int k=0;//赋值的时候变量
		//d循环次数最大数的位数
		while(m<d){
			for(int i=0;i<a.length;i++){
				int lsd=(a[i]/div)%10;
				temp[lsd][length[lsd]]=a[i];
				length[lsd]++;
			}
			for(int i=0;i<10;i++){
				if(length[i]!=0){
					for(int j=0;j<length[i];j++)
						a[k++]=temp[i][j];
					}
				length[i]=0;
			}
			System.out.println(Arrays.toString(a));
			m++;
			div*=10;
			k=0;
		}
	}