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54 lines
1.6 KiB
54 lines
1.6 KiB
6 months ago
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/**
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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 "../utils/common.hpp"
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/* Hash search (array) */
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int hashingSearchArray(unordered_map<int, int> map, int target) {
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// Hash table's key: target element, value: index
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// If the hash table does not contain this key, return -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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/* Hash search (linked list) */
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ListNode *hashingSearchLinkedList(unordered_map<int, ListNode *> map, int target) {
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// Hash table key: target node value, value: node object
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// If the key is not in the hash table, return 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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/* Hash search (array) */
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vector<int> nums = {1, 5, 3, 2, 4, 7, 5, 9, 10, 8};
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// Initialize hash table
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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: element, value: index
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}
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int index = hashingSearchArray(map, target);
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cout << "The index of target element 3 is " << index << endl;
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/* Hash search (linked list) */
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ListNode *head = vecToLinkedList(nums);
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// Initialize hash table
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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: node value, value: node
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head = head->next;
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}
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ListNode *node = hashingSearchLinkedList(map1, target);
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cout << "The corresponding node object for target node value 3 is " << node << endl;
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return 0;
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}
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