python实现的链表，包括插入、查找、删除操作
#!/usr/bin/python
class linknode():
def __init__(self,k,n=None):
self.key=k;
self.next=n;
def createlist(): #创建链表
n=raw_input("enter the num of nodes");
n=int(n);
if n<1 :
return ;
else :
a=raw_input("enter the key");
head=linknode(k=a);
if n is 1:
return head;
else :
p=head;
for i in range(1,n):
a=raw_input("enter a key");
t=linknode(k=a);
p.next=t;
p=t;
return head;
def printlist(head): #打印链表
p=head;
while p!= None:
print p.key;
p=p.next;
def listlen(head): #计算链表长度
c=0;
p=head;
while p!= None:
c=c+1;
p=p.next;
return c;
def insert(head,n): #插入元素
if n<1 or n>listlen(head) :
return ;
p=head;
if n is 1:
a=raw_input("enter a key");
t=linknode(k=a);
t.next=head;
head=t;
else :
for i in range(1,n-1):
p=p.next;
a=raw_input("enter a key");
t=linknode(k=a);
t.next=p.next;
p.next=t;
return head;
def dellist(head,n): #删除
if n<1 or n>listlen(head):
return head;
elif n is 1:
head=head.next;
else:
p=head;
for i in range(1,n-1):
p=p.next;
q=p.next;
p.next=q.next;
return head;
def findlist(head,n): # 查找
p=head;
if p is None:
return ;
while(p!=None):
if p.key is repr(n):
print "find it";
return 1;
else:
p=p.next;
if p is None:
print "not found";