python实现归并排序和快速排序

归并排序

def MergerSort(lists):
    if len(lists)<=1:
        return lists
    num=int(len(lists)/2)
    left=MergerSort(lists[:num])
    right=MergerSort(lists[num:])
    return Merge(left,right)
def Merge(left,right):
    r,l=0,0
    result=[]
    while l<len(left) and r<len(right):
        if left[l]<=right[r]:
            result.append(left[l])
            l+=1
        else:
            result.append(right[r])
            r+=1
    result+=list(left[l:])
    result+=list(right[r:])
    return result
print(MergerSort([22,3,2,8,65,8,9,1,4,3]))

快速排序

def quick_sort(data):    
    """快速排序"""    
    if len(data) >= 2:  # 递归入口及出口        
        mid = data[len(data)//2]  # 选取基准值,也可以选取第一个或最后一个元素        
        left, right = [], []  # 定义基准值左右两侧的列表        
        data.remove(mid)  # 从原始数组中移除基准值        
        for num in data:            
            if num >= mid:                
                right.append(num)            
            else:                
                left.append(num)        
        return quick_sort(left) + [mid] + quick_sort(right)    
    else:        
        return data
 
# 示例:
array = [2,3,5,7,1,4,6,15,5,2,7,9,10,15,9,17,12]
print(quickSort(array))
# 输出为[1, 2, 2, 3, 4, 5, 5, 6, 7, 7, 9, 9, 10, 12, 15, 15, 17]

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转载自blog.csdn.net/mieleizhi0522/article/details/88894272