Sorting Algorithm in Python

copy and learn

Quick sort

Python实现快速排序算法.

def quick_sort(lists,i,j):
    if i >= j:
        return list
    pivot = lists[i]
    low = i
    high = j
    while i < j:
        while i < j and lists[j] >= pivot:
            j -= 1
        lists[i]=lists[j]
        while i < j and lists[i] <=pivot:
            i += 1
        lists[j]=lists[i]
    lists[j] = pivot
    quick_sort(lists,low,i-1)
    quick_sort(lists,i+1,high)
    return lists

if __name__=="__main__":
    lists=[30,24,5,58,18,36,12,42,39]
    print("排序前的序列为：")
    for i in lists:
        print(i,end =" ")
    print("\n排序后的序列为：")
    for i in quick_sort(lists,0,len(lists)-1):
        print(i,end=" ")

Time Complexity in average: O(nlogn)
Space Complexity in average: O(logn)

Principle: find the correct place of each number one by one

Bubble Sort

Runoob.

def bubbleSort(arr):
    n = len(arr)
 
    # 遍历所有数组元素
    for i in range(n):
        # Last i elements are already in place
        for j in range(0, n-i-1):
 
            if arr[j] > arr[j+1] :
                arr[j], arr[j+1] = arr[j+1], arr[j]
 
arr = [64, 34, 25, 12, 22, 11, 90]
bubbleSort(arr)
print ("排序后的数组:")
print(arr)

Time Complexity in average: O(n²)
Space Complexity in average: O(1)
Principle: only switch with the next number