feat(LeetCode): Solve onlinePlatform/leetcode/leetcoding_challenge/2025/may2025/week3/longest_unequal_adjacent_groups_subsequence_i.cpp

Author: htbkoo

src/onlinePlatform/leetcode/leetcoding_challenge/2025/may2025/week3/longest_unequal_adjacent_groups_subsequence_i.cpp

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+// https://leetcode.com/problems/longest-unequal-adjacent-groups-subsequence-i/description/?envType=daily-question&envId=2025-05-15
+
+#include <algorithm>
+#include <vector>
+#include <queue>
+#include <set>
+#include <limits>
+#include <map>
+#include <unordered_set>
+#include <unordered_map>
+#include <iterator>
+#include <sstream>
+#include <iostream> // includes cin to read from stdin and cout to write to stdout
+using namespace std; // since cin and cout are both in namespace std, this saves some text
+
+class Solution {
+public:
+    vector<string> getLongestSubsequence(vector<string> &words, vector<int> &groups) {
+        int NO_PREV = -1;
+
+        vector<pair<int, int> > best(words.size());
+        for (int i = 0; i < words.size(); ++i) {
+            best[i] = pair{words[i].size(), NO_PREV};
+        }
+
+        int bestIdx = 0;
+        for (int i = 0; i < words.size(); ++i) {
+            for (int j = 0; j < i; ++j) {
+                if (groups[i] == groups[j]) {
+                    continue;
+                }
+                int lengthJ = best[j].first + words[i].size();
+                if (lengthJ > best[i].first) {
+                    best[i] = pair{lengthJ, j};
+                }
+                if (best[i].first > best[bestIdx].first) {
+                    bestIdx = i;
+                }
+            }
+        }
+
+        deque<string> answer;
+        while (bestIdx != NO_PREV) {
+            answer.push_front(words[bestIdx]);
+            bestIdx = best[bestIdx].second;
+        }
+
+        // return vector(begin(answer), end(answer));
+        return {begin(answer), end(answer)};
+    }
+};
+
+int main() {
+    Solution soln;
+    vector<string> words{"a", "b", "c", "d"};
+    vector groups{1, 0, 1, 1};
+
+    auto result = soln.getLongestSubsequence(words, groups);
+    for (auto w: result) {
+        cout << w << " ";
+    }
+    cout << endl;
+
+    return 0;
+}