phone_number: ...

cpp/phone-number/phone_number.cpp

@@ -0,0 +1,26 @@
+#include "phone_number.h"
+
+#include <algorithm>
+#include <ctype>
+
+using namespace std;
+
+phone_number::phone_number(const string &str)
+{
+    static const string invalid_number = "0000000000";
+}
+
+string phone_number::number() const
+{
+    return number_;
+}
+
+string phone_number::area_code() const
+{
+    return area_code_;
+}
+
+phone_number::operator string() const
+{
+    return number_;
+}

cpp/phone-number/phone_number.h

@@ -0,0 +1,18 @@
+#pragma once
+
+#include <string>
+
+class phone_number
+{
+    std::string area_code_;
+    std::string number_;
+
+public:
+
+    phone_number(const std::string&);
+
+    std::string number() const;
+    std::string area_code() const;
+
+    operator std::string() const;
+};