链表的python实现

单链表的增删改查

class ListNode(object):
    def __init__(self, value=0, next=None):
        self.value = value
        self.next = next


def BuildListNode(l: list):
    head = ListNode()
    temp = head
    for elem in l:
        temp.next = ListNode(elem)
        temp = temp.next
    return head


def BuildListNodeReverse(l: list):
    head = ListNode()
    for elem in l:
        temp = head.next
        head.next = ListNode(elem, temp)
    return head


def PrintListNode(head: ListNode):
    cur = head
    print('_________')
    while cur.next:
        cur = cur.next
        print(cur.value)


def Insert(head: ListNode, i, elem):
    assert i >= 0
    elem = ListNode(elem)
    cur = head
    while i != 0:
        i -= 1
        cur = cur.next
        if not cur:
            return False
    temp = cur.next
    cur.next = elem
    elem.next = temp
    return True


def Find(head: ListNode, i):
    assert i >= 0
    cur = head.next
    while i != 0:
        cur = cur.next
        i -= 1
        if not cur:
            return False
    return cur.value


def Delete(head: ListNode, i):
    assert i >= 0
    cur = head
    while i != 0:
        cur = cur.next
        i -= 1
        if not cur:
            return False
    cur.next = cur.next.next
    return True