本文实例讲述了python列表操作的方法。分享给大家供大家参考。

具体实现方法如下：

复制代码 代码如下:class Node:
   \”\”\”Single node in a data structure\”\”\”
 
   def __init__(self, data):
      \”\”\”Node constructor\”\”\”
      
      self._data = data
      self._nextNode = None
    
   def __str__(self):
      \”\”\”Node data representation\”\”\”
 
      return str(self._data)    
 
class List:
   \”\”\”Linked list\”\”\”
 
   def __init__(self):
      \”\”\”List constructor\”\”\”
 
      self._firstNode = None
      self._lastNode = None
 
   def __str__(self):
      \”\”\”List string representation\”\”\”
 
      if self.isEmpty():
         return \”empty\”
 
      currentNode = self._firstNode
      output = []
 
      while currentNode is not None:
         output.append(str(currentNode._data))
         currentNode = currentNode._nextNode
 
      return \” \”.join(output)    
 
   def insertAtFront(self, value):
      \”\”\”Insert node at front of list\”\”\”
 
      newNode = Node(value)
 
      if self.isEmpty():  # List is empty
         self._firstNode = self._lastNode = newNode
      else:   # List is not empty
         newNode._nextNode = self._firstNode
         self._firstNode = newNode
        
   def insertAtBack(self, value):
      \”\”\”Insert node at back of list\”\”\”
 
      newNode = Node(value)
 
      if self.isEmpty():  # List is empty
         self._firstNode = self._lastNode = newNode
      else:  # List is not empty
         self._lastNode._nextNode = newNode
         self._lastNode = newNode
 
   def removeFromFront(self):
      \”\”\”Delete node from front of list\”\”\”
 
      if self.isEmpty():  # raise exception on empty list
         raise IndexError, \”remove from empty list\”
 
      tempNode = self._firstNode
 
      if self._firstNode is self._lastNode:  # one node in list
         self._firstNode = self._lastNode = None
      else:
         self._firstNode = self._firstNode._nextNode
 
      return tempNode
 
   def removeFromBack(self):
      \”\”\”Delete node from back of list\”\”\”
 
      if self.isEmpty():  # raise exception on empty list
         raise IndexError, \”remove from empty list\”
     
      tempNode = self._lastNode
 
      if self._firstNode is self._lastNode:  # one node in list
         self._firstNode = self._lastNode = None
      else:
         currentNode = self._firstNode
 
         # locate second-to-last node
         while currentNode._nextNode is not self._lastNode:
               currentNode = currentNode._nextNode
               
         currentNode._nextNode = None
         self._lastNode = currentNode
 
      return tempNode
    
   def isEmpty(self):
      \”\”\”Returns true if List is empty\”\”\”
 
      return self._firstNode is None

希望本文所述对大家的Python程序设计有所帮助。