Python daily delicious (32)-Python data structure and algorithm heap sorting

ArticleDirectory

• 1. Select sort
• 2. Heap sorting
• 3. Efficiency

1. Select sort

The sorting principle is to first select the smallest number, exchange with the first number, and then switch from the second number to the second number ,......

Def Selection_sort ( Data ):
For I In Range ( Len ( Data ) - 1 ):
Min = Data [ I ]
K = I
For J In Range ( I , Len ( Data )):
If Data [ J ] < Min :
Min = Data [ J ]
K = J
If I <> K :
Data [ I ], Data [ K ] = Data [ K ], Data [ I ]

2. Heap sorting

The heap sorting principle adjusts arrays to heaps, exchanges the heap top element with the last element, removes the last node from the heap, and then adjusts the remaining arrays to heaps, then swap the heap element and the last element ......

Def Heap_adjust ( Data , S , M ):
If 2 * S > M :
Return
Temp = S - 1
If Data [ 2 * S - 1 ] > Data [ Temp ]:
Temp = 2 * S - 1
If 2 * S <= M - 1 And Data [ 2 * S ] > Data [ Temp ]:
Temp = 2 * S
If Temp <> S - 1 :
Data [ S - 1 ], Data [ Temp ] = Data [ Temp ], Data [ S - 1 ]
Heap_adjust ( Data , Temp + 1 , M )
Def Heap_sort ( Data ):
M = Len ( Data ) / 2
For I In Range ( M , 0 , - 1 ):
Heap_adjust ( Data , I , Len ( Data ))
Data [ 0 ], Data [ - 1 ] = Data [ - 1 ], Data [ 0 ]
For N In Range ( Len ( Data ) - 1 , 1 , - 1 ):
Heap_adjust ( Data , 1 , N )
Data [ 0 ], Data [ N - 1 ] = Data [ N - 1 ], Data [ 0 ]

3. Efficiency

The heap sorting efficiency is quite high. The result is as follows:

Selection_sort 0:00:02. 219000
Heap_sort 0:00:00. 157000

 

Python daily delicious series (total)

Python daily delicious (30)-Fast sorting of Python data structures and algorithms

Python daily delicious (31)-insert sorting of Python data structures and algorithms

Python daily delicious (32)-Python data structure and algorithm heap sorting

Python every day (33)-five minutes to understand metaclasses [go]

Python daily delicious (34)-decorators