2020.4.20之算法系列：1.快速排序的思想

10(0)

5(1)

6(2)

84(3)

55(4)

1(5)

5(6)

22(7)

48(8)

20(9)

 利用第一个数作为基准值，temp = 10；high--；直到arr[6]=5;则此时arr[0]=5;

low++直到arr[3] = 84;则arr[6] = 84;high--直到arr[5] = 1,则arr[3] = 1;low++直到arr[4]=55，arr[5] = 55;

arr[4] = 10;

5

5

6

1

10

55

84

22

48

20

void partion(vector<int>& nums,int left,int right){
    if(left<right){
        int temp = nums[left];
        int low = left;
        int high = right;
        while(low<high){
            while(low<high&&nums[high]<temp){
                high--;
        }
        nums[low] = nums[high];
        while(low<high&&nums[low]<=temp){
            low++;
        }
        nums[high] = nums[low];
        }
        nums[low] = temp;
        partion(nums,left,low-1);
        partion(nums,low+1,right);
    }
}