leetcode706-设计哈希映射

设计哈希映射

• 哈希+链表

class MyHashMap {
    class Pair{
        int key;
        int value;
        public Pair(int key, int value){
            this.key = key;
            this.value = value;
        }
    }
    LinkedList arr[] = new LinkedList[1024];
    final static int total = 769;
    public MyHashMap() {
        for(int i = 0; i < 769; i++){
            arr[i] = new LinkedList<Pair>();
        }
    }
    
    public void put(int key, int value) {
        int hash = key % total;
        Iterator<Pair> it = arr[hash].iterator();
        while(it.hasNext()){
            Pair p = it.next();
            if(p.key == key){
                p.value = value;
                return;
            }
        }
        arr[hash].add(new Pair(key, value));
    }
    
    public int get(int key) {
        int hash = key % total;
        Iterator<Pair> it = arr[hash].iterator();
        while(it.hasNext()){
            Pair p = it.next();
            if(p.key == key){
                return p.value;
            }
        }
        return -1;
    }
    
    public void remove(int key) {
        int hash = key % total;
        Iterator<Pair> it = arr[hash].iterator();
        while(it.hasNext()){
            Pair p = it.next();
            if(p.key == key){
                it.remove();
                return;
            }
        }
    }
}