数据结构与算法排序算法java描述

public class TestSort {
	public static void selectSort(int[] arr) {
		
		for(int i = 0;i<arr.length;i++) {
			int temp = arr[i];
			int flag = i;
			for(int j = i+1;j<arr.length;j++) {
				if(arr[j] < temp) {
					temp = arr[j];
					flag = j;
				}
			}
			if(flag != i) {
				arr[flag] = arr[i];
				arr[i] = temp;
			}
			
		}
	}
	
	public static void insertSort(int[] arr) {
		
		if( arr!= null) {
			for(int i = 1;i<arr.length;i++) {
				int temp = arr[i];
				int j = i;
				if(arr[j-1]>temp) {
					while(j>=1&&arr[j-1]>temp) {     //选择的那个数比前面的数要小，
						//则就将其跟前面的数一个一个比较，知道碰到比这个数还要小的，将其放在这
						arr[j] = arr[j-1];
						j--;
					}
				}
				arr[j] = temp;
				
			}
		}
	}
	
	public static void bubbleSort(int[] arr) {
		for(int i = 0;i<arr.length - 1;i++) {
			for(int j = arr.length - 1;j>i;j--) {
				if(arr[j] < arr[j-1]) {
					int temp = arr[j];
					arr[j] = arr[j-1];
					arr[j-1] = temp;
				}
			}
		}
	}
	public static void merge(int[] a,int s,int m,int t) {
		int i,j,k;
		int n1 = m - s + 1;
		int n2 = t - m;
		int[] left = new int[n1];
		int[] right = new int[n2];
		for(i = 0,k = s;i<n1;i++,k++) {
			left[i] = a[k];
		}
		for(i = 0,k = m + 1;i<n2;i++,k++) {
			right[i] = a[k];
		}
		for(i = 0,j = 0,k = s;i < n1 && j < n2;) {
			a[k++] = (left[i]<right[j])?left[i++]:right[j++];
		}
		while(i<n1) {
			a[k++] = left[i++];
		}
		while(j<n2) {
			a[k++] = right[j++];
		}
	}
	
	public static void mergeSort(int[] a,int s,int t) {
		if(s<t) {
			int q = (s + t)/2;
			mergeSort(a, s, q);
			mergeSort(a, q+1, t);
			merge(a, s, q, t);
		}
	}
	
	//快速排序
	public static void quickSort(int[] a,int low,int high) {
		if(low >= high) {
			return;
		}
		int i = low,j = high;
		int pivot = a[i];    //每次取第一个元素作为分割值
		while(i < j) {
			while(i < j&&a[j] > pivot) {
				j--;
			}
			if(i<j) {
				a[i++] = a[j];
			}
			while(i<j&&a[i]<pivot) {
				i++;
			}
			if(i<j) {
				a[j--] = a[i];
			}
		}
		a[i] = pivot;
		quickSort(a, low, i - 1);
		quickSort(a, i + 1, high);
	}
	
	//希尔排序
	public static void shellSort(int[] a) {
		int len = a.length;
		int h;    //h为跨度
		int i,j;
		int temp;
		for(h = len/2;h>0;h /= 2) {
			for(i = h;i<len;i++) {
				temp = a[i];   
				j = i - h;    //同一组中上一个元素的下标
				while(j>0 && temp < a[j]) {      //当前数值小于同一组中的上一个元素
					a[j + h] = a[j];
					j = j - h;
				}
				a[j + h] = temp;     //j+h,因为上面减的小于0了  = = 
			}
		}
	}
	
	
	//堆排序
	public static void adjustMinHeap(int[] a,int pos,int len) {    //将pos位置处的结点调整为小顶堆
		int child;
		int temp;
		
		for(temp = a[pos];2*pos+1<=len;pos = child) {     //迭代该节点下的所有子节点
			child = 2*pos+1;
			if(child<len&&a[child]>a[child+1]) {
				child++;
			}
			if(a[child]<temp) {      //如果某一个结点的子节点小与该节点的值，则替换之
				a[pos] = a[child];
			}else break;     //此时已经到头了
			
		}
		a[pos] = temp;     //此时的pos为child的值，这样做就把该节点和小与该节点的子节点交换的值
		
	}
	
	public static void heapSort(int[] a) {
		int len = a.length;
		for(int i = len/2 - 1;i >= 0;i--) {    //将整个二叉树调整成为小顶堆
			adjustMinHeap(a, i, len - 1);
		}
		for(int i = len - 1;i>=0;i--) {   //交换堆顶位置和最后一个位置处的值，然后再调整成为小顶堆
			int temp = a[0];    
			a[0] = a[i];
			a[i] = temp;
			adjustMinHeap(a, 0, i - 1);
			
		}
	}
	public static void main(String[] args) {
		/*int[] a = {21,32,123,12,4543,12,354235,2,4,32,525432,425253,4,23,5,35};
		selectSort(a);
		for (int i : a) {
			System.out.println(i);
		}*/
		/*MyInt firstNum = new MyInt(5);
		MyInt secondNum = new MyInt(10);
		swap(firstNum, secondNum);
		
		System.out.println(firstNum.data);
		System.out.println(secondNum.data);*/
		int[] a = {21,32,123,12,4543,12,354235,2,4,32,525432,425253,4,23,5,35};
//		bubbleSort(a);
		//mergeSort(a, 0, a.length - 1);
		//quickSort(a, 0, a.length - 1);
//		shellSort(a);
		heapSort(a);
		System.out.println(Arrays.toString(a));
		
	}