Description#
Design a HashMap without using any built-in hash table libraries.
Implement the MyHashMap class:
MyHashMap() initializes the object with an empty map.void put(int key, int value) inserts a (key, value) pair into the HashMap. If the key already exists in the map, update the corresponding value.int get(int key) returns the value to which the specified key is mapped, or -1 if this map contains no mapping for the key.void remove(key) removes the key and its corresponding value if the map contains the mapping for the key.
Example 1:
Input
["MyHashMap", "put", "put", "get", "get", "put", "get", "remove", "get"]
[[], [1, 1], [2, 2], [1], [3], [2, 1], [2], [2], [2]]
Output
[null, null, null, 1, -1, null, 1, null, -1]
Explanation
MyHashMap myHashMap = new MyHashMap();
myHashMap.put(1, 1); // The map is now [[1,1]]
myHashMap.put(2, 2); // The map is now [[1,1], [2,2]]
myHashMap.get(1); // return 1, The map is now [[1,1], [2,2]]
myHashMap.get(3); // return -1 (i.e., not found), The map is now [[1,1], [2,2]]
myHashMap.put(2, 1); // The map is now [[1,1], [2,1]] (i.e., update the existing value)
myHashMap.get(2); // return 1, The map is now [[1,1], [2,1]]
myHashMap.remove(2); // remove the mapping for 2, The map is now [[1,1]]
myHashMap.get(2); // return -1 (i.e., not found), The map is now [[1,1]]
Constraints:
0 <= key, value <= 106- At most
104 calls will be made to put, get, and remove.
Solutions#
Solution 1#
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| class MyHashMap:
def __init__(self):
self.data = [-1] * 1000001
def put(self, key: int, value: int) -> None:
self.data[key] = value
def get(self, key: int) -> int:
return self.data[key]
def remove(self, key: int) -> None:
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)
|
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| class MyHashMap {
private int[] data = new int[1000001];
public MyHashMap() {
Arrays.fill(data, -1);
}
public void put(int key, int value) {
data[key] = value;
}
public int get(int key) {
return data[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);
*/
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| class MyHashMap {
public:
int data[1000001];
MyHashMap() {
memset(data, -1, sizeof data);
}
void put(int key, int value) {
data[key] = value;
}
int get(int key) {
return data[key];
}
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);
*/
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| type MyHashMap struct {
data []int
}
func Constructor() MyHashMap {
data := make([]int, 1000010)
for i := range data {
data[i] = -1
}
return MyHashMap{data}
}
func (this *MyHashMap) Put(key int, value int) {
this.data[key] = value
}
func (this *MyHashMap) Get(key int) int {
return this.data[key]
}
func (this *MyHashMap) Remove(key int) {
this.data[key] = -1
}
/**
* Your MyHashMap object will be instantiated and called as such:
* obj := Constructor();
* obj.Put(key,value);
* param_2 := obj.Get(key);
* obj.Remove(key);
*/
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| class MyHashMap {
data: Array<number>;
constructor() {
this.data = new Array(10 ** 6 + 1).fill(-1);
}
put(key: number, value: number): void {
this.data[key] = value;
}
get(key: number): number {
return this.data[key];
}
remove(key: number): void {
this.data[key] = -1;
}
}
/**
* Your MyHashMap object will be instantiated and called as such:
* var obj = new MyHashMap()
* obj.put(key,value)
* var param_2 = obj.get(key)
* obj.remove(key)
*/
|
