/*
*将发生碰撞的key都放在同一个链表node上,用一个链表串起来
*/
class MyHashMap {
final ListNode[] nodes = new ListNode[10000];
public void put(int key, int value) {
int i = idx(key);
if (nodes[i] == null)
nodes[i] = new ListNode(-1, -1);
ListNode prev = find(nodes[i], key);
//prev.next == null 意味着链表nodes[i]没有key这个结点,prev指向链表的最后一个结点
if (prev.next == null)
prev.next = new ListNode(key, value);
else prev.next.val = value;
}
public int get(int key) {
int i = idx(key);
if (nodes[i] == null)
return -1;
ListNode node = find(nodes[i], key);
return node.next == null ? -1 : node.next.val;
}
public void remove(int key) {
int i = idx(key);
if (nodes[i] == null) return;
ListNode prev = find(nodes[i], key);
if (prev.next == null) return;
prev.next = prev.next.next;
}
int idx(int key) { return Integer.hashCode(key) % nodes.length;}
//find()函数返回bucket链表key结点上一个结点,如果bucket链表不存在key结点,则返回bucket链表最后一个结点
ListNode find(ListNode bucket, int key) {
ListNode node = bucket, prev = null;
while (node != null && node.key != key) {
prev = node;
node = node.next;
}
return prev;
}
class ListNode {
int key, val;
ListNode next;
ListNode(int key, int val) {
this.key = key;
this.val = val;
}
}
}
Design HashMap
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转载自blog.csdn.net/qq_28808697/article/details/103035492
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