七大基本排序算法之堆排序

package Sort;

import java.io.IOException;

import Input.InputString;

public class HeapSort {

    /**
     * @param args
     */
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        try {
            String str = InputString.getString();
            String[] s = str.split(" ");
            int[] a = new int[s.length+1];
            for(int i = 1; i<=s.length;i++){
                a[i] = Integer.parseInt(s[i-1]);
            }
            heapSort(a);
            for(int i = 1; i<a.length;i++){
                System.out.print(a[i]+" ");
            }
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public static void heapAdjust(int[] a, int begin,int end){
        int temp = a[begin];
        for(int i = 2*begin; i <= end; i = 2*i){
            if(i < end && a[i] < a[i+1]){
                i++;
            }
            if(temp >= a[i]){
                break;
            }
            a[begin] = a[i];
            begin = i;
        }
        a[begin] = temp;
    }

    public static void heapSort(int[] a){
        for(int i = a.length/2; i > 0; i--){
            heapAdjust(a, i, a.length-1);
        }
        for(int i = a.length-1; i > 1; i--){
            int temp = a[1];
            a[1] = a[i];
            a[i] = temp;
            heapAdjust(a, 1, i-1);
        }   
    }
}

import java.io.IOException;
import Input.InputString;

/**
 * 堆排序
 * @author xiaomi
 * 2012.4.1
 */
public class HeapSort { 
    private static int[] heap;
    public static void main(String[] args) throws IOException{
        String s = InputString.getString();
        String[] str = s.split(" ");
        heap = new int[str.length+1];//从下标1开始算起
        for(int i = 0;i < str.length;i++){
            heap[i+1] = Integer.parseInt(str[i]);
        }
        heapSort();
        for(int i = 1;i < heap.length;i++){
            System.out.print(heap[i]+" ");
        }
    }

    public static void heapSort(){
        createHeap();
        for(int i = 1;i < heap.length;i++){
            ajustHeap(i);
        }
    }

    //每加入一个节点就要向上筛选一次
    public static void createHeap(){
        for(int i = 2; i < heap.length;i++){
            for(int j = i; j/2>=1;j/=2){
                if(heap[j]>heap[j/2]){
                    int temp = heap[j];
                    heap[j] = heap[j/2];
                    heap[j/2] = temp;
                }
            }
        }
    }

    //每移走一个节点就要向下调整一次
    public static void ajustHeap(int k){
        int temp = heap[1];
        heap[1] = heap[heap.length-k];
        heap[heap.length-k] = temp;
        int i = 1;
        while((2*i) < heap.length-k){
            if((2*i+1) < heap.length-k){
                if(heap[i] > heap[2*i] && heap[i] > heap[2*i+1]){
                    break;
                }
                else{//与较大的一个子节点交换
                    if(heap[2*i] < heap[2*i+1]){
                        int a = heap[i];
                        heap[i] = heap[2*i+1];
                        heap[2*i+1] = a;
                        i = 2*i+1;
                    }else{
                        int a = heap[i];
                        heap[i] = heap[2*i];
                        heap[2*i] = a;
                        i = 2*i;
                    }
                }
            }else{//不存在右节点的时候
                if(heap[i] > heap[2*i]){
                    break;
                }
                else{
                    int a = heap[i];
                    heap[i] = heap[2*i];
                    heap[2*i] = a;
                    i = 2*i;
                }
            }   
        }
    }
}