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* docs: add Japanese documents (`ja/docs`) * docs: add Japanese documents (`ja/codes`) * docs: add Japanese documents * Remove pythontutor blocks in ja/ * Add an empty at the end of each markdown file. * Add the missing figures (use the English version temporarily). * Add index.md for Japanese version. * Add index.html for Japanese version. * Add missing index.assets * Fix backtracking_algorithm.md for Japanese version. * Add avatar_eltociear.jpg. Fix image links on the Japanese landing page. * Add the Japanese banner. --------- Co-authored-by: krahets <krahets@163.com>
56 lines
1.7 KiB
C++
56 lines
1.7 KiB
C++
/**
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* File: permutations_ii.cpp
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* Created Time: 2023-04-24
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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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/* バックトラッキングアルゴリズム：順列 II */
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void backtrack(vector<int> &state, const vector<int> &choices, vector<bool> &selected, vector<vector<int>> &res) {
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// 状態の長さが要素数と等しくなったら、解を記録
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if (state.size() == choices.size()) {
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res.push_back(state);
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return;
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}
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// すべての選択肢を走査
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unordered_set<int> duplicated;
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for (int i = 0; i < choices.size(); i++) {
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int choice = choices[i];
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// 剪定：要素の重複選択を許可せず、等しい要素の重複選択も許可しない
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if (!selected[i] && duplicated.find(choice) == duplicated.end()) {
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// 試行：選択を行い、状態を更新
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duplicated.emplace(choice); // 選択された要素値を記録
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selected[i] = true;
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state.push_back(choice);
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// 次のラウンドの選択に進む
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backtrack(state, choices, selected, res);
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// 回退：選択を取り消し、前の状態に復元
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selected[i] = false;
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state.pop_back();
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}
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}
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}
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/* 順列 II */
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vector<vector<int>> permutationsII(vector<int> nums) {
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vector<int> state;
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vector<bool> selected(nums.size(), false);
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vector<vector<int>> res;
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backtrack(state, nums, selected, res);
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return res;
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}
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/* ドライバーコード */
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int main() {
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vector<int> nums = {1, 1, 2};
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vector<vector<int>> res = permutationsII(nums);
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cout << "入力配列 nums = ";
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printVector(nums);
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cout << "すべての順列 res = ";
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printVectorMatrix(res);
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return 0;
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} |