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数据结构复习(一)排序算法

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package algorithm.sort;

import java.util.Random;

public class Sort {
	private static Random rand = new Random();
	public void BubbleSort(int[] a, int length) {
		for (int i = 0; i < length; i++)
			for (int j = i + 1; j < length; j++) {
				if (a[i] >= a[j]) {
					int temp = a[i];
					a[i] = a[j];
					a[j] = temp;
				}
			}
	}
	public void InsertSort(int [] a,int length){
		int temp,j;
		for(int i=0;i<length;i++){
			 temp = a[i];
			 j = i-1;
			while(j>=0&&temp<a[j]){
				a[j+1] = a[j];
				j--;
				
			}
			a[j+1] = temp;
		}
	}
	public void BinSort(int[] t, int length) {
		int key, i, j, low, high, mid;
		for (i = 1; i < length; i++) {
			low = 0;
			high = i - 1;
			key = t[i];
			while (low <= high) {
				mid = (low + high) / 2;
				if (key < t[mid]) {
					high = mid - 1;
				} else {
					low = mid + 1;
				}
			}
			for (j = i; j > high + 1; j--) {
				t[j] = t[j - 1];
			}
			t[high + 1] = key;
		}
	}

	private void MAX_HEAPIFY(int[] a, int i, int heapSize) {
		int left = i * 2;
		int right = i * 2 + 1;
		int largest;
		if (left <= heapSize && a[left] > a[i]) {
			largest = left;
		} else {
			largest = i;
		}
		if (right <= heapSize && a[right] > a[largest]) {
			largest = right;
		}
		if (largest != i) {
			int temp = a[i];
			a[i] = a[largest];
			a[largest] = temp;
			MAX_HEAPIFY(a, largest, heapSize);
		}
	}

	private void BUILD_MAX_HEAP(int[] a, int heapSize) {
		for (int i = a.length / 2; i >= 0; i--) {
			MAX_HEAPIFY(a, i, heapSize);
		}
	}

	public void HeapSort(int[] a) {
		BUILD_MAX_HEAP(a, a.length - 1);
		int heapSize = a.length - 1;
		for (int i = a.length - 1; i >= 1; i--) {
			int temp = a[0];
			a[0] = a[i];
			a[i] = temp;
			heapSize = heapSize - 1;
			MAX_HEAPIFY(a, 0, heapSize);
		}
	}

	public void QuickSort(int[] a, int p, int r) {
		if (p < r) {
			int q = partition(a, p, r);
			QuickSort(a, p, q - 1);
			QuickSort(a, q + 1, r);
		}
	}

	private int partition(int[] a, int p, int r) {
		int i = p + rand.nextInt(r - p + 1);
		swap(a,p,i);
		int pivot = a[p];
		int low = p;
		int high = r;
		while(low<high){
			while(low<high&&a[high]>pivot){
				high--;
			}
			if(low<high){
				a[low]=a[high];
				low++;
			}
			while(low<high&&a[low]<pivot){
				low++;
			}
			if(low<high){
				a[high]=a[low];
				high--;
			}

		}
		a[low] = pivot;
		return low;
	}
	private static void swap(int x[],int a,int b){
		int temp = x[a];
		x[a] = x[b];
		x[b] = temp;
	}
	public void mergeSort(int[] a,int[] temp,int low,int high){
		if(low < high){
			int mid = (low+high)/2;
			mergeSort(a,temp,low,mid);
			mergeSort(a,temp,mid+1,high);
			merge(a,temp,low,mid,high);
			
		}
	}
	private void merge(int[] a,int[] temp,int low,int mid,int high){
		
		for(int i=low;i<=high;i++){
			temp[i] = a[i];
		}
		int i=low,j=mid+1,k=low;
		while((i<=low)&&(j<=high)){
			if(temp[i]<=temp[j]){
				a[k++] = temp[i++];
			}else{
				a[k++] = temp[j++];
			}
		}
		while(i<=mid){
			a[k++] = temp[i++];
		}
		while(j<=high){
			a[k++] = temp[j++];
		}
	}
	public static void main(String[] args) {
		Sort sort = new Sort();
		int a[] = { 7, 4, 3, 8, 9, 65, 23, 99, 15, 2, 0, 47 };
		int temp[] = new int[a.length];
		// sort.BubbleSort(a, a.length);
		sort.InsertSort(a, a.length);
		//sort.BinSort(a, a.length);
		//sort.QuickSort(a,0,a.length-1);
		// sort.HeapSort(a);
		//sort.mergeSort(a, temp,0, a.length-1);
		for (int i = 0; i < a.length; i++) {
			System.out.print(a[i] + " ");
		}
	}
}

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