java 堆排序

Posted 2021-01-10 沙漠里的小鱼

    public  void heapSort(int[] arry){
        int len= arry.length -1 ;
        for(int i = (len-1)/2 ;i>=0 ;i--){
            buildHeap(arry,i,len);
        }
        for(int i = len ;i >0 ;i--){
            swap(arry,0 ,i) ;
            buildHeap(arry,0,i-1);
        }
        System.out.println("arry数组"+arry);

    }


    public  void  buildHeap(int[] arry,int index,int len){
        int temp=arry[index];
        for(int i = 2*index+1 ;i<=len ;i=i*2+1){
            if (i < len  && arry[i] < arry[i+1]){
                i++ ;
            }
            if (temp >= arry[i]){
                break;
            }
            arry[index] =arry[i];
            index = i ;
        }
        arry[index] = temp ;
    }


    public void swap(int[] arry ,int left ,int right){
        int temp =arry[left] ;
        arry[left] =arry[right] ;
        arry[right] = temp ;
    }