排序算法总结

public static void quickSort(int[] arr,int begin,int end){
        if(begin>=end) return; //不可缺少？？？   递归的结束条件
        int idx=partion(arr,begin,end);
        quickSort(arr,begin,idx-1);
        quickSort(arr,idx+1,end);
    }
    private static int partion(int[] arr,int lo,int hi){
        int key=arr[lo];
        while(lo<hi){
            while(arr[hi]>=key&&lo<hi){
                hi--;
            }
            arr[lo]=arr[hi];
            while(arr[lo]<=key&&lo<hi){
                lo++;
            }
            arr[hi]=arr[lo];
        }
        arr[hi]=key;
        return hi;
    }
    

public static void InsertSort(int[] arr){
        for(int j=1;j<arr.length;j++){
            int i=j-1;
            int key=arr[j];
            while(i>0&&arr[i]>key){
                arr[i+1]=arr[i];
                i--;
            }
            arr[i+1]=key;
            
        }
    }
    
    public static void MergeSort(int[] arr,int low,int high){
        int mid=low+(high-low)/2;
        MergeSort(arr,low,mid);
        MergeSort(arr,mid+1,high);
        Merge(arr,low,mid,high);
    }
    private static void Merge(int[] arr,int low,int mid,int high){
        int[] temp=new int[high-low+1];
        int i=low;
        int j=mid+1;
        int k=0;
        while(i<mid&&j<high){
            if(arr[i]<arr[j]){
                temp[k++]=arr[i];
            }else{
                temp[k++]=arr[j];
            }           
        }
        while(i<mid){
            temp[k++]=arr[i++];
        }
        while(j<high){
            temp[k++]=arr[j++];
        }
        for(int m=0;m<temp.length;m++){
            arr[m]=temp[m];
        }
    }