Merge pull request #185 from AlgoLeadMe/51-9kyo-hwang

51-9kyo-hwang

9-kyo-hwang/Data Structure/21944 문제 추천 시스템 Version 2.cpp

@@ -0,0 +1,179 @@
+#include <iostream>
+#include <set>
+
+using namespace std;
+
+class Database
+{
+public:
+    int Recommend1(int G, int x)
+    {
+        if(x == 1)
+        {
+            return Recommend1P(G);
+        }
+        else if(x == -1)
+        {
+            return Recommend1N(G);
+        }
+    }
+
+    int Recommend2(int x)
+    {
+        if(x == 1)
+        {
+            return Recommend2P();
+        }
+        else if(x == -1)
+        {
+            return Recommend2N();
+        }
+    }
+
+    int Recommend3(int x, int L)
+    {
+        if(x == 1)
+        {
+            return Recommend3P(L);
+        }
+        else if(x == -1)
+        {
+            return Recommend3N(L);
+        }
+    }
+
+    void Add(int P, int L, int G)
+    {
+        ProblemByLevel[L].emplace(P);
+        ProblemByLevelAndGroup[L][G].emplace(P);
+        Problems[P] = {L, G};
+    }
+
+    void Solved(int P)
+    {
+        ProblemByLevel[Problems[P].first].erase(P);
+        ProblemByLevelAndGroup[Problems[P].first][Problems[P].second].erase(P);
+    }
+
+private:
+    set<int> ProblemByLevel[101];
+    set<int> ProblemByLevelAndGroup[101][101];
+    pair<int, int> Problems[100001];
+
+    int Recommend1P(int G)
+    {
+        for(int L = 100; L >= 1; --L)
+        {
+            if(!ProblemByLevelAndGroup[L][G].empty())
+            {
+                return *(--ProblemByLevelAndGroup[L][G].end());
+            }
+        }
+    }
+
+    int Recommend1N(int G)
+    {
+        for(int L = 1; L <= 100; ++L)
+        {
+            if(!ProblemByLevelAndGroup[L][G].empty())
+            {
+                return *ProblemByLevelAndGroup[L][G].begin();
+            }
+        }
+    }
+
+    int Recommend2P()
+    {
+        for(int L = 100; L >= 1; --L)
+        {
+            if(!ProblemByLevel[L].empty())
+            {
+                return *(--ProblemByLevel[L].end());
+            }
+        }
+    }
+
+    int Recommend2N()
+    {
+        for(int L = 1; L <= 100; ++L)
+        {
+            if(!ProblemByLevel[L].empty())
+            {
+                return *ProblemByLevel[L].begin();
+            }
+        }
+    }
+
+    int Recommend3P(int L)
+    {
+        for(; L <= 100; ++L)
+        {
+            if(!ProblemByLevel[L].empty())
+            {
+                return *ProblemByLevel[L].begin();
+            }
+        }
+        return -1;
+    }
+
+    int Recommend3N(int L)
+    {
+        for(L -= 1; L >= 1; --L)
+        {
+            if(!ProblemByLevel[L].empty())
+            {
+                return *(--ProblemByLevel[L].end());
+            }
+        }
+        return -1;
+    }
+};
+
+int main()
+{
+    cin.tie(nullptr)->sync_with_stdio(false);
+
+    Database* DB = new Database();
+
+    int N; cin >> N;
+    while(N--)
+    {
+        int P, L, G; cin >> P >> L >> G;
+        DB->Add(P, L, G);
+    }
+
+    int M; cin >> M;
+    while(M--)
+    {
+        string Command; cin >> Command;
+        if(Command == "recommend")  // find Max/Min in Category G
+        {
+            int G, x; cin >> G >> x;
+            cout << DB->Recommend1(G, x) << "\n";
+        }
+        else if(Command == "recommend2")  // find Max/Min any Category
+        {
+            int x; cin >> x;
+            cout << DB->Recommend2(x) << "\n";
+        }
+        else if(Command == "recommend3")  // find lower bound
+        {
+            int x, L; cin >> x >> L;
+            cout << DB->Recommend3(x, L) << "\n";
+        }
+        else if(Command == "add")
+        {
+            int P, L, G; cin >> P >> L >> G;
+            DB->Add(P, L, G);
+        }
+        else if(Command == "solved")
+        {
+            int P; cin >> P;
+            DB->Solved(P);
+        }
+    }
+
+    delete DB;
+
+    return 0;
+}

9-kyo-hwang/README.md

@@ -50,4 +50,5 @@
 | 47차시 | 2024.5.16  | Brute Force                | [14500 테트로미노](https://www.acmicpc.net/problem/14503)    | [#171](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/171) |
 | 48차시 | 2024.5.20  | Shortest Path              | [1162 도로포장](https://www.acmicpc.net/problem/1162)    | [#175](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/175) |
 | 49차시 | 2024.5.23  | Data Structure             | [21939 문제 추천 시스템 Version 1](https://www.acmicpc.net/problem/21939)    | [#179](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/179) |
-| 50차시 | 2024.5.25  | Graph Traversal            | [26146 즉흥 여행 (Easy)](https://www.acmicpc.net/problem/26146)    | [#182](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/182) |
+| 50차시 | 2024.5.25  | Graph Traversal            | [26146 즉흥 여행 (Easy)](https://www.acmicpc.net/problem/26146)    | [#182](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/182) |
+| 51차시 | 2024.5.30  | Data Structure             | [21944 문제 추천 시스템 Version 2](https://www.acmicpc.net/problem/21944)    | [#185](https://github.com/AlgoLeadMe/AlgoLeadMe-3/pull/185) |