Python與資料結構
一、順序表
-
存儲位置 L O C ( a i + 1 ) LOC(a_{i+1}) LOC(ai+1)和第i個資料元素的存儲位置為 L O C ( a i ) LOC(a_i) LOC(ai)之間滿足下列關系
L O C ( a a + 1 ) = L O C ( a i ) + l LOC(a_{a+1}) = LOC(a_i)+l LOC(aa+1)=LOC(ai)+l
- 線性表的第 i i i個資料元素 a i a_i ai的存儲位置為
L O C ( a i ) = L O C ( a 1 ) + ( i − 1 ) ∗ l LOC(a_i) = LOC(a_1)+(i-1)*l LOC(ai)=LOC(a1)+(i−1)∗l
- 尾端加入元素,時間複雜度為O(1)
- 非保序的加入元素(不常見),O(1)
- 保序的元素加入,時間複雜度為O(n)
- 順序表元素外置,存儲表的位址,然後再找到存儲的資料
- python中順序表 是用操作append,pop等
二、連結清單
2.1 單向連結清單
産生資料結構,定義為類
- 定義結點類
class Node(object):
"""
建立結點類
"""
def __init__(self,elem):
self.elem = elem
self.next = None
# 初始為空值
- 定義單連結清單類
class SingleLinkList(object):
"""單連結清單"""
def __init__(self,node=None):
"""
指向頭結點,預設為空值
:param node:
"""
self.__head = node
def is_empty(self):
"""連結清單是否為空"""
return self.__head == None
def length(self):
"""連結清單長度"""
# cur 指針用來移動周遊結點
cur = self.__head
# count 記錄數量
count = 0 # count初始化為0
while cur != None:
count += 1
cur = cur.next
# count = 1
# cur.next != None
return count
def travel(self):
"""周遊整個連結清單"""
cur = self.__head
while cur != None:
print(cur.elem,end = " ")
cur = cur.next
print("\t")
def add(self,item):
"""連結清單頭部添加元素,頭插法"""
node = Node(item)
node.next = self.__head
self.__head = node
def append(self,item):
"""連結清單尾部添加元素,尾插法"""
node = Node(item)
if self.is_empty():
self.__head = node
else:
cur = self.__head
while cur.next != None:
cur = cur.next
cur.next = node
def insert(self,pos,item):
"""指定位置添加元素
:param pos from 0
"""
if pos<=0:
self.add(item)
elif pos>(self.length()-1):
self.append(item)
else:
pre = self.__head
count = 0
while count< pos-1:
pre = pre.next
count += 1
# 當循環結束後,pre指向pos-1位置
node = Node(item)
node.next = pre.next
pre.next = node
def remove(self,item):
"""删除節點"""
cur = self.__head
pre = None
while cur != None:
if cur.elem == item:
# 先判斷此結點是否為頭結點
# 頭結點:
if cur == self.__head:
self.__head = cur.next
break
else:
pre.next = cur.next
break
else:
pre = cur
cur = cur.next
def search(self,item):
"""查找結點是否存在"""
cur = self.__head
while cur != None:
if cur.elem == item:
return True
else:
cur = cur.next
return False
class Node(object):
"""
建立結點類
"""
def __init__(self,elem):
self.elem = elem
self.next = None
class SingleLinkList(object):
"""單連結清單"""
def __init__(self,node=None):
"""
指向頭結點,預設為空值
:param node:
"""
self.__head = node
def is_empty(self):
"""連結清單是否為空"""
return self.__head == None
def length(self):
"""連結清單長度"""
# cur 指針用來移動周遊結點
cur = self.__head
# count 記錄數量
count = 0 # count初始化為0
while cur != None:
count += 1
cur = cur.next
# count = 1
# cur.next != None
return count
def travel(self):
"""周遊整個連結清單"""
cur = self.__head
while cur != None:
print(cur.elem,end = " ")
cur = cur.next
print("\t")
def add(self,item):
"""連結清單頭部添加元素,頭插法"""
node = Node(item)
node.next = self.__head
self.__head = node
def append(self,item):
"""連結清單尾部添加元素,尾插法"""
node = Node(item)
if self.is_empty():
self.__head = node
else:
cur = self.__head
while cur.next != None:
cur = cur.next
cur.next = node
def insert(self,pos,item):
"""指定位置添加元素
:param pos from 0
"""
if pos<=0:
self.add(item)
elif pos>(self.length()-1):
self.append(item)
else:
pre = self.__head
count = 0
while count< pos-1:
pre = pre.next
count += 1
# 當循環結束後,pre指向pos-1位置
node = Node(item)
node.next = pre.next
pre.next = node
def remove(self,item):
"""删除節點"""
cur = self.__head
pre = None
while cur != None:
if cur.elem == item:
# 先判斷此結點是否為頭結點
# 頭結點:
if cur == self.__head:
self.__head = cur.next
break
else:
pre.next = cur.next
break
else:
pre = cur
cur = cur.next
def search(self,item):
"""查找結點是否存在"""
cur = self.__head
while cur != None:
if cur.elem == item:
return True
else:
cur = cur.next
return False
# node = Node(100)
if __name__ == "__main__":
ll = SingleLinkList()
print(ll.is_empty())
print(ll.length())
ll.append(10)
print(ll.is_empty())
print(ll.length())
ll.append(2)
ll.append(3)
ll.append(4)
ll.append(5)
ll.append(6)
ll.add(100)
ll.insert(-1,9)
ll.insert(2,1000)
ll.insert(10,10000)
ll.travel()
ll.remove(100)
ll.travel()
ll.remove(10000)
ll.travel()
2.2 雙向連結清單
class Node(object):
"""
結點
"""
def __init__(self,item):
self.elem = item
self.next = None
self.prev = None
class DoubleLinkList(object):
"""雙連結清單"""
def __init__(self,node=None):
"""
指向頭結點,預設為空值
:param node:
"""
self.__head = node
def is_empty(self):
"""連結清單是否為空"""
return self.__head is None
def length(self):
"""連結清單長度"""
# cur 指針用來移動周遊結點
cur = self.__head
# count 記錄數量
count = 0 # count初始化為0
while cur != None:
count += 1
cur = cur.next
# count = 1
# cur.next != None
return count
def travel(self):
"""周遊整個連結清單"""
cur = self.__head
while cur != None:
print(cur.elem,end = " ")
cur = cur.next
print("\t")
# 以上和singlelinklist操作一樣
def add(self,item):
"""連結清單頭部添加元素,頭插法"""
node = Node(item)
node.next = self.__head
self.__head = node
node.next.prev = node
def append(self,item):
"""連結清單尾部添加元素,尾插法"""
node = Node(item)
if self.is_empty():
self.__head = node
else:
cur = self.__head
while cur.next != None:
cur = cur.next
cur.next = node
node.prev = cur
def insert(self,pos,item):
"""指定位置添加元素
:param pos from 0
"""
if pos<=0:
self.add(item)
elif pos>(self.length()-1):
self.append(item)
else:
cur = self.__head
count = 0
while count< pos:
cur = cur.next
count += 1
# 當循環結束後,cur指向pos位置
node = Node(item)
node.next = cur
node.prev = cur.prev
cur.prev.next = node
cur.prev = node
def remove(self,item):
"""删除節點"""
cur = self.__head
while cur != None:
if cur.elem == item:
# 先判斷此結點是否為頭結點
# 頭結點:
if cur == self.__head:
self.__head = cur.next
if cur.next:
# 判斷連結清單是否隻有一個結點
cur.next.prev = None
cur.next.prev = None
else:
cur.prev.next = cur.next
if cur.next:
cur.next.prev = cur.prev
break
else:
cur = cur.next
def search(self,item):
"""查找結點是否存在"""
cur = self.__head
while cur != None:
if cur.elem == item:
return True
else:
cur = cur.next
return False
if __name__ == "__main__":
ll = DoubleLinkList()
print(ll.is_empty())
print(ll.length())
ll.append(10)
print(ll.is_empty())
print(ll.length())
ll.append(2)
ll.append(3)
ll.append(4)
ll.append(5)
ll.append(6)
ll.add(100)
ll.insert(-1,9)
ll.insert(2,1000)
ll.insert(10,10000)
ll.travel()
ll.remove(100)
ll.travel()
ll.remove(10000)
ll.travel()
2.3 單向循環連結清單
# -*- coding:utf-8 -*-
# Author : XuQiao
class Node(object):
"""
建立結點類
"""
def __init__(self,elem):
self.elem = elem
self.next = None
class SingleCycleLinkList(object):
"""單向循環連結清單"""
def __init__(self,node=None):
"""
指向頭結點,預設為空值
:param node:
"""
self.__head = node
if node:
node.next = node
def is_empty(self):
"""連結清單是否為空"""
return self.__head == None
def length(self):
"""連結清單長度"""
if self.is_empty():
return 0
# cur 指針用來移動周遊結點
cur = self.__head
# count 記錄數量
count = 1
while cur.next != self.__head:
count += 1
cur = cur.next
return count
def travel(self):
"""周遊整個連結清單"""
if self.is_empty():
return
cur = self.__head
while cur.next != self.__head:
print(cur.elem)
cur = cur.next
# 退出循環,cur指向尾結點,但尾結點的元素未列印
print(cur.elem,end=" ")
print("\t")
def add(self,item):
"""連結清單頭部添加元素,頭插法"""
node = Node(item)
if self.is_empty():
self.__head = node
self.__head.next = self.__head
return
cur = self.__head
while cur.next != self.__head:
cur = cur.next
node.next = self.__head
self.__head = node
cur.next = self.__head
def append(self,item):
"""連結清單尾部添加元素,尾插法"""
node = Node(item)
cur = self.__head
if self.is_empty():
self.__head = node
self.__head.next = self.__head
return
while cur.next != self.__head:
cur = cur.next
node.next = cur.next
cur.next = node
def insert(self,pos,item):
"""指定位置添加元素
:param pos from 0
"""
if pos<=0:
self.add(item)
elif pos>(self.length()-1):
self.append(item)
else:
pre = self.__head
count = 0
while count< pos-1:
pre = pre.next
count += 1
# 當循環結束後,pre指向pos-1位置
node = Node(item)
node.next = pre.next
pre.next = node
def remove(self,item):
"""删除節點"""
if self.is_empty():
return
cur = self.__head
pre = None
while cur.next != self.__head:
if cur.elem == item:
# 先判斷此結點是否為頭結點
# 頭結點:
if cur == self.__head:
# 頭結點的情況
# 找尾結點
rear = self.__head
while rear.next != self.__head:
rear = rear.next
self.__head = cur.next
rear.next = self.__head
# self.__head = cur.next
else: # 中間結點
pre.next = cur.next
return
else:
pre = cur
cur = cur.next
# 退出循環,cur指向尾結點
if cur.elem == item:
if cur == self.__head:
# 連結清單隻有一個結點
self.__head = None
else:
pre.next = cur.next
def search(self,item):
"""查找結點是否存在"""
if self.is_empty():
return False
cur = self.__head
while cur.next != self.__head:
if cur.elem == item:
return True
else:
cur = cur.next
if cur.elem == item:
return True
return False
# node = Node(100)
if __name__ == "__main__":
ll = SingleCycleLinkList()
print(ll.is_empty())
print(ll.length())
ll.append(10)
print(ll.is_empty())
print(ll.length())
ll.append(2)
ll.append(3)
ll.append(4)
ll.append(5)
ll.append(6)
ll.add(100)
ll.insert(-1,9)
ll.insert(2,1000)
ll.insert(10,10000)
ll.travel()
ll.remove(100)
ll.travel()
ll.remove(10000)
ll.travel()