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src/Ausgabenverwaltung.cpp

@@ -1,9 +1,13 @@
 #include <iostream>
 #include <list>
 #include <string>
+#include <map>
 
 using namespace std;
 
+/**
+ * \brief invoice, which contains number, amount, month of creation and category.
+ */
 class invoice
 {
 private:
@@ -15,11 +19,17 @@ public:
 	static const char* categories[];
 	static const char* months[];
 
-	invoice(int number, double amount, unsigned short month, int category) : number_(number), amount_(amount),
+	invoice(const int number, const double amount, const unsigned short month, const int category) : number_(number),
-	                                                                         month_(month), category_(category)
+	                                                                                                 amount_(amount),
+	                                                                                                 month_(month),
+	                                                                                                 category_(category)
 	{
 	}
 
+	/**
+	 * \brief Get number of invoice.
+	 * \return number
+	 */
 	int get_number() const
 	{
 		return number_;
@@ -35,10 +45,15 @@ public:
 		return category_;
 	}
 
+	double get_amount() const
+	{
+		return amount_;
+	}
+
 	void print() const
 	{
 		cout << "  Rechnung: " << number_ << endl;
-		cout << "  Betrag: " << amount_ << "€" << endl;
+		cout << "  Betrag: " << amount_ << " Euro" << endl;
 		cout << "  Monat: " << months[month_] << endl;
 		cout << "  Kategorie: " << categories[category_] << endl;
 	}
@@ -57,8 +72,31 @@ public:
 	bool operator !=(const invoice& e) const { return !operator==(e); }
 };
 
-const char* invoice::categories[] = {"Tanken", "Nahrungsmittel", "Reinigungsmittel", "Urlaub", "Haustiere", "Bekleidung", "Wohnen", "Versicherung"};
+const char* invoice::categories[] = {
-const char* invoice::months[] = {"Januar", "Februar", "März", "April", "Mai", "Juni", "Juli", "August", "September", "Oktober", "November", "Dezember"};
+	"Tanken",
+	"Nahrungsmittel",
+	"Reinigungsmittel",
+	"Urlaub",
+	"Haustiere",
+	"Bekleidung",
+	"Wohnen",
+	"Versicherung"
+};
+
+const char* invoice::months[] = {
+	"Januar",
+	"Februar",
+	"März",
+	"April",
+	"Mai",
+	"Juni",
+	"Juli",
+	"August",
+	"September",
+	"Oktober",
+	"November",
+	"Dezember"
+};
 
 template <typename T>
 T ask_question(const string& question)
@@ -70,23 +108,25 @@ T ask_question(const string& question)
 	return value;
 }
 
-list<invoice> invoices;
-
 void create_invoice();
 
-void output_invoices_order_by_month();
+void invoices_ordered_by_month();
 
 void delete_invoice();
 
+void sum_invoices_per_category();
+
 bool compare_month_ascending(const invoice& first, const invoice& second)
 {
 	return first.get_month() < second.get_month();
 }
 
+list<invoice> invoices;
+int invoice_serial_number;
+
 int main()
 {
-	auto end_program = false;
+	while (true)
-	while (!end_program)
 	{
 		system("cls");
 		cout << "Ausgabenverwaltung (" << invoices.size() << " Rechnungen)" << endl << endl;
@@ -105,23 +145,21 @@ int main()
 			create_invoice();
 			break;
 		case 2:
-			output_invoices_order_by_month();
+			invoices_ordered_by_month();
 			break;
 		case 3:
-			//TODO
+			sum_invoices_per_category();
 			break;
 		case 4:
 			delete_invoice();
 			break;
 		case 0:
-			end_program = true;
+			return 0;
-			break;
 		default:
 			cout << "Unerlaubte Eingabe" << endl;
 			system("pause");
 		}
 	}
-	return 0;
 }
 
 int get_month();
@@ -132,7 +170,7 @@ void create_invoice()
 	system("cls");
 	cout << "Eine neue Rechnung erstellen." << endl;
 	cout << "------------------------------------" << endl;
-	const auto invoice_no = invoices.empty() ? 1 : invoices.back().get_number() + 1;
+	const auto invoice_no = ++invoice_serial_number;
 	const auto amount = ask_question<double>("Bitte geben Sie den Betrag in Euro ein.");
 	const auto month = get_month();
 	const auto category = get_category();
@@ -141,7 +179,7 @@ void create_invoice()
 }
 
 
-void output_invoices_order_by_month()
+void invoices_ordered_by_month()
 {
 	system("cls");
 	cout << "Alle Rechnungen nach Monat sortiert:" << endl;
@@ -171,6 +209,22 @@ void delete_invoice()
 	system("pause");
 }
 
+void sum_invoices_per_category()
+{
+	map<int, double> sums;
+	for (auto invoice : invoices)
+	{
+		sums[invoice.get_category()] = sums[invoice.get_category()] += invoice.get_amount();
+	}
+	for (const auto sum : sums)
+	{
+		cout << "    Kategorie: " << invoice::categories[sum.first] << endl;
+		cout << "    Summe: " << sum.second << " Euro" << endl;
+		cout << "------------------------------------" << endl;
+	}
+	system("pause");
+}
+
 int get_month()
 {
 	while (true)