1 #!/usr/bin/env python3 2 3 class LNode(object): 4 def __init__(self, elem, next_=None): 5 self.elem = elem 6 self.next = next_ 7 8 class ListError(ValueError): 9 pass 10 11 class LList(object): 12 def __init__(self): 13 self.head = None 14 self.num = 0 15 16 def is_empty(self): 17 return self.head is None 18 19 def count(self): 20 return self.num 21 22 def prepend(self, elem): 23 self.head = LNode(elem, self.head) 24 self.num += 1 25 26 def pop(self): 27 if self.head is None: 28 raise ListError 29 e = self.head.elem 30 self.head = self.head.next 31 self.num -= 1 32 return e 33 34 def append(self, elem): 35 if self.head is None: 36 self.head = LNode(elem, self.head) 37 self.num += 1 38 return 39 p = self.head 40 while p.next: 41 p = p.next 42 p.next = LNode(elem) 43 self.num += 1 44 45 def pop_last(self): 46 if self.head is None: 47 raise ListError 48 p = self.head 49 if p.next is None: 50 e = p.elem 51 self.head = None 52 self.num -= 1 53 return e 54 while p.next.next: 55 p = p.next 56 e = p.next.elem 57 p.next = None 58 self.num -= 1 59 return e 60 61 def bianli(self): 62 p = self.head 63 li = [] 64 while p: 65 li.append(p.elem) 66 p = p.next 67 return li 68 69 def reverse(self): 70 li = self.bianli() 71 sl = LList() 72 for i in li: 73 sl.prepend(i) 74 return sl 75 76 if __name__ == '__main__': 77 l = LList() 78 l.append(1)
79 l.prepend(2) 80 l.pop_last() 81 l.append(3) 82 l.append(4) 83 l.append(5) 84 li = l.bianli() 85 print(li) 86 sl = l.reverse() 87 li = sl.bianli() 88 print(li) 8889
结果：
[2,3,4,5]
[5,4,3,2]
好久没写数据结构了 回顾一下