不使用任何内建的哈希表库设计一个哈希映射
具体地说，你的设计应该包含以下的功能
put(key, value)：向哈希映射中插入(键,值)的数值对。如果键对应的值已经存在，更新这个值。get(key)：返回给定的键所对应的值，如果映射中不包含这个键，返回-1。remove(key)：如果映射中存在这个键，删除这个数值对。
示例：
MyHashMap hashMap = new MyHashMap(); hashMap.put(1, 1); hashMap.put(2, 2); hashMap.get(1); // 返回 1 hashMap.get(3); // 返回 -1 (未找到) hashMap.put(2, 1); // 更新已有的值 hashMap.get(2); // 返回 1 hashMap.remove(2); // 删除键为2的数据 hashMap.get(2); // 返回 -1 (未找到)
注意：
- 所有的值都在
[1, 1000000]的范围内。 - 操作的总数目在
[1, 10000]范围内。 - 不要使用内建的哈希库。
数组实现。
class MyHashMap:
def __init__(self):
"""
Initialize your data structure here.
"""
self.data = [-1] * 1000001
def put(self, key: int, value: int) -> None:
"""
value will always be non-negative.
"""
self.data[key] = value
def get(self, key: int) -> int:
"""
Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key
"""
return self.data[key]
def remove(self, key: int) -> None:
"""
Removes the mapping of the specified value key if this map contains a mapping for the key
"""
self.data[key] = -1
# Your MyHashMap object will be instantiated and called as such:
# obj = MyHashMap()
# obj.put(key,value)
# param_2 = obj.get(key)
# obj.remove(key)class MyHashMap {
private int[] data;
/** Initialize your data structure here. */
public MyHashMap() {
data = new int[1000001];
Arrays.fill(data, -1);
}
/** value will always be non-negative. */
public void put(int key, int value) {
data[key] = value;
}
/** Returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key */
public int get(int key) {
return data[key];
}
/** Removes the mapping of the specified value key if this map contains a mapping for the key */
public void remove(int key) {
data[key] = -1;
}
}
/**
* Your MyHashMap object will be instantiated and called as such:
* MyHashMap obj = new MyHashMap();
* obj.put(key,value);
* int param_2 = obj.get(key);
* obj.remove(key);
*/