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54 lines
1.5 KiB
C++
54 lines
1.5 KiB
C++
/**
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* File: hashing_search.cpp
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* Created Time: 2022-11-25
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* Author: Krahets (krahets@163.com)
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*/
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#include "../include/include.hpp"
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/* 哈希查找（数组） */
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int hashingSearch(unordered_map<int, int> map, int target) {
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// 哈希表的 key: 目标元素，value: 索引
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// 若哈希表中无此 key ，返回 -1
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if (map.find(target) == map.end())
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return -1;
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return map[target];
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}
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/* 哈希查找（链表） */
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ListNode* hashingSearch1(unordered_map<int, ListNode*> map, int target) {
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// 哈希表的 key: 目标结点值，value: 结点对象
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// 若哈希表中无此 key ，返回 nullptr
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if (map.find(target) == map.end())
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return nullptr;
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return map[target];
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}
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/* Driver Code */
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int main() {
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int target = 3;
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/* 哈希查找（数组） */
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vector<int> nums = { 1, 5, 3, 2, 4, 7, 5, 9, 10, 8 };
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// 初始化哈希表
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unordered_map<int, int> map;
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for (int i = 0; i < nums.size(); i++) {
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map[nums[i]] = i; // key: 元素，value: 索引
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}
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int index = hashingSearch(map, target);
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cout << "目标元素 3 的索引 = " << index << endl;
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/* 哈希查找（链表） */
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ListNode* head = vecToLinkedList(nums);
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// 初始化哈希表
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unordered_map<int, ListNode*> map1;
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while (head != nullptr) {
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map1[head->val] = head; // key: 结点值，value: 结点
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head = head->next;
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}
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ListNode* node = hashingSearch1(map1, target);
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cout << "目标结点值 3 的对应结点对象为 " << node << endl;
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return 0;
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}
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