java版的就是传统的用low和high两个指针去写
package smile;
import java.util.Arrays;
public class quickSort {
public static void main(String args[]) {
int[] num = {10,2,12,3,5,1,7,8,9,20};
// sort(num,0,10);
int len = num.length;
quick(num,0,len-1);
System.out.println(Arrays.toString(num));
}
// public static void sort(int[] nums,int begin,int end) {
// int key = nums[begin];
// int count=0;
// int temp;
// for(int i=begin;i<end;i++) {
// if(nums[i]<=key) {
// temp = nums[i];
// nums[i] =nums[count];
// nums[count] = temp;
// count++;
// }
// }
// for(int i=0;i<count;i++) {
// System.out.println(nums[i]);
// }
// System.out.println("满足条件的个数:"+count);
// System.out.println("不满足条件的个数:"+(nums.length-count));
// }
// 快排
// 分区函数
public static int divPart(int[] nums,int low,int high) {
int flag = nums[low];
while(low<high) {
while(low<high&&nums[high]>=flag) {
--high;
}
nums[low] = nums[high];
while(low<high&&nums[low]<=flag) {
++low;
}
nums[high] = nums[low];
}
nums[low] = flag;
return low;
}
// 递归排序
public static void quick(int []num,int low,int high) {
if(low<high) {
int middle = divPart(num,low,high);
quick(num,low,middle);
quick(num,middle+1,high);
}
}
}
python不用low,high指针
# 不用low以及high指针进行快排
# 分区函数
def divison(list,start,end):
# 初始化
count=1
key=list[start]
# 将满足条件的元素放在列表前边
for i in range(start+1,end+1):
if list[i]<=key:
temp = list[i]
list[i] = list[start+count]
list[start+count] = temp
count+=1
# 将元素前移一位
for i in range(0,count-1):
list[start+i] = list[start+i+1]
# 将key(基准元素)值放在空位上
list[start+count-1] = key
# 返回基准元素下标
return start+count-1
# 递归调用快排算法
def quick_sort1(list,start,end):
if start<end:
index = divison(list,start,end)
quick_sort1(list,0,index-1)
quick_sort1(list,index+1,end)
# 封装
def quick_sort(list):
quick_sort1(list,0,len(list)-1)
if __name__ == '__main__':
list = [1,5,23,-1,6,9,2,3]
quick_sort(list)
print(list)