LeetCode 706. Design HashMap (设计哈希映射)

题目标签：HashMap

　　题目让我们设计一个 hashmap， 有put， get， remove 功能。

　　建立一个 int array， index 是key， 值是 value，具体看code。

 

Java Solution:

Runtime: 76 ms, faster than 27.53% 

Memory Usage: 58.2 MB, less than 31.57%

完成日期：03/18/2019

关键点：int array

class MyHashMap {

    int [] map;
    /** Initialize your data structure here. */
    public MyHashMap() {
        map = new int[1000001];
        Arrays.fill(map, -1);
    }
    
    /** value will always be non-negative. */
    public void put(int key, int value) {
        map[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 map[key];
    }
    
    /** Removes the mapping of the specified value key if this map contains a mapping for the key */
    public void remove(int key) {
        map[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);
 */

参考资料：N/A

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