[LeetCode&Python] Problem 706. Design HashMap

Posted chiyeung

tags:

篇首语:本文由小常识网(cha138.com)小编为大家整理,主要介绍了[LeetCode&Python] Problem 706. Design HashMap相关的知识,希望对你有一定的参考价值。

Design a HashMap without using any built-in hash table libraries.

To be specific, your design should include these functions:

  • put(key, value) : Insert a (key, value) pair into the HashMap. If the value already exists in the HashMap, update the value.
  • get(key): Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key.
  • remove(key) : Remove the mapping for the value key if this map contains the mapping for the key.


Example:

MyHashMap hashMap = new MyHashMap();
hashMap.put(1, 1);          
hashMap.put(2, 2);         
hashMap.get(1);            // returns 1
hashMap.get(3);            // returns -1 (not found)
hashMap.put(2, 1);          // update the existing value
hashMap.get(2);            // returns 1 
hashMap.remove(2);          // remove the mapping for 2
hashMap.get(2);            // returns -1 (not found) 


Note:

    • All keys and values will be in the range of [0, 1000000].
    • The number of operations will be in the range of [1, 10000].
    • Please do not use the built-in HashMap library. 

 

class MyHashMap(object):

    def __init__(self):
        """
        Initialize your data structure here.
        """
        self._data={}

    def put(self, key, value):
        """
        value will always be non-negative.
        :type key: int
        :type value: int
        :rtype: void
        """
        self._data[key]=value

    def get(self, key):
        """
        Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key
        :type key: int
        :rtype: int
        """
        if key in self._data:
            return self._data[key]
        else:
            return -1

    def remove(self, key):
        """
        Removes the mapping of the specified value key if this map contains a mapping for the key
        :type key: int
        :rtype: void
        """
        if key in self._data:
            del self._data[key]
        


# Your MyHashMap object will be instantiated and called as such:
# obj = MyHashMap()
# obj.put(key,value)
# param_2 = obj.get(key)
# obj.remove(key)

  



以上是关于[LeetCode&Python] Problem 706. Design HashMap的主要内容,如果未能解决你的问题,请参考以下文章

C++&Python描述 LeetCode C++&Python描述 LeetCode 剑指 Offer 22. 链表中倒数第k个节点

[LeetCode&Python] Problem 202. Happy Number

[LeetCode&Python] Problem 520. Detect Capital

[LeetCode&Python] Problem 383. Ransom Note

[LeetCode&Python] Problem 458. Poor Pigs

[LeetCode&Python] Problem 682. Baseball Game