Finalized the implementation

generator.h

@@ -0,0 +1,24 @@
+#pragma once
+
+#include "impl_generator.h"
+
+#include <memory>
+
+class ProgramOptions;
+
+class Generator
+{
+    public:
+
+    static constexpr int NO_MORE_NUMBERS = -1;
+
+    Generator(const ProgramOptions& options);
+    ~Generator() = default;
+
+    int get_next_num();
+
+    private:
+    const ProgramOptions& m_options;
+    std::unique_ptr<ImplGenerator> impl = nullptr;
+
+};