feat(C++): Add 2349

C++/2349-DesignANumberContainerSystem/Solution.cpp

@@ -0,0 +1,58 @@
+#include <cstddef>
+#include <set>
+#include <unordered_map>
+
+using namespace std;
+/**
+ * Seems to be a many-to-one relationship between Buckets/Containers and
+ * Numbers.
+ * Each Container can store only one Number, but each Number may be stored in
+ * multiple Containers.
+ *
+ * 1 <= index, number <= 10^9. => 4MB of integers possible => unordered_map
+ * should be used instead of an array.
+ *
+ * Naively, seems like two unordered_map is sufficient.
+ * One for bucket -> number
+ * The other for number -> {bucket1, ...}
+ *
+ * For the number -> buckets, use an ordered Set.
+ */
+class NumberContainers {
+ private:
+  std::unordered_map<int, int> containers;
+  std::unordered_map<int, std::set<int>> numbers;
+
+ public:
+  NumberContainers() {}
+
+  void change(int index, int number) {
+    auto iter = containers.find(index);
+    if (iter != containers.end()) {
+      int original = iter->second;
+      numbers[original].erase(index);
+
+      if (numbers[original].empty()) {
+        numbers.erase(original);
+      }
+    }
+    containers[index] = number;
+    numbers[number].insert(index);
+  }
+
+  int find(int number) {
+    auto iter = numbers.find(number);
+    if (iter == numbers.end()) {
+      return -1;
+    }
+
+    return *(iter->second).begin();
+  }
+};
+
+/**
+ * Your NumberContainers object will be instantiated and called as such:
+ * NumberContainers* obj = new NumberContainers();
+ * obj->change(index,number);
+ * int param_2 = obj->find(number);
+ */

README.md

@@ -412,6 +412,7 @@ Now solving in C++. Like it.
 | 2331 | EvaluateBooleanBinaryTree                                        |         [![Rust](assets/rust.svg)](Rust/2331-EvaluateBooleanBinaryTree/Solution.rs) [![C++](assets/c++.svg)](C++/2331-EvaluateBooleanBinaryTree/Solution.cpp)         |
 | 2334 | SubarrayWithElementsGreaterThanVaryingThreshold                  |                                    [![C++](assets/c++.svg)](C++/2334-SubarrayWithElementsGreaterThanVaryingThreshold/Solution.cpp)                                    |
 | 2336 | SmallestNumberInInfiniteSet                                      |                                              [![C++](assets/c++.svg)](C++/2336-SmallestNumberInInfiniteSet/Solution.cpp)                                              |
+| 2349 | DesignANumberContainerSystem                                     |                                             [![C++](assets/c++.svg)](C++/2349-DesignANumberContainerSystem/Solution.cpp)                                              |
 | 2373 | LargestLocalValuesInAMatrix                                      |                                             [![Rust](assets/rust.svg)](Rust/2373-LargestLocalValuesInAMatrix/Solution.rs)                                             |
 | 2392 | BuildAMatrixWithConditions                                       |                                              [![C++](assets/c++.svg)](C++/2392-BuildAMatrixWithConditions/Solution.cpp)                                               |
 | 2393 | CountStrictlyIncreasingSubarrays                                 |                                           [![C++](assets/c++.svg)](C++/2393-CountStrictlyIncreasingSubarrays/Solution.cpp)                                            |