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/**
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* File: hashing_search.dart
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* Created Time: 2023-05-12
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* Author: Jefferson (JeffersonHuang77@gmail.com)
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*/
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import 'dart:collection';
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import '../utils/list_node.dart';
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/* 雜湊查詢（陣列） */
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int hashingSearchArray(Map<int, int> map, int target) {
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// 雜湊表的 key: 目標元素，value: 索引
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// 若雜湊表中無此 key ，返回 -1
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if (!map.containsKey(target)) {
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return -1;
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}
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return map[target]!;
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}
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/* 雜湊查詢（鏈結串列） */
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ListNode? hashingSearchLinkedList(Map<int, ListNode> map, int target) {
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// 雜湊表的 key: 目標節點值，value: 節點物件
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// 若雜湊表中無此 key ，返回 null
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if (!map.containsKey(target)) {
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return null;
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}
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return map[target]!;
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}
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/* Driver Code */
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void main() {
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int target = 3;
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/* 雜湊查詢（陣列） */
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List<int> nums = [1, 5, 3, 2, 4, 7, 5, 9, 10, 8];
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// 初始化雜湊表
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Map<int, int> map = HashMap();
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for (int i = 0; i < nums.length; i++) {
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map.putIfAbsent(nums[i], () => i); // key: 元素，value: 索引
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}
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int index = hashingSearchArray(map, target);
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print('目標元素 3 的索引 = $index');
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/* 雜湊查詢（鏈結串列） */
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ListNode? head = listToLinkedList(nums);
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// 初始化雜湊表
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Map<int, ListNode> map1 = HashMap();
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while (head != null) {
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map1.putIfAbsent(head.val, () => head!); // key: 節點值，value: 節點
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head = head.next;
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}
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ListNode? node = hashingSearchLinkedList(map1, target);
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print('目標節點值 3 的對應節點物件為 $node');
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}
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