Added Backend Classes and FUnctions for an working Game. But lacking Implementations

API/Models/DataClasses/SixDigitInt.cs

@@ -0,0 +1,20 @@
+namespace API.Models.DataClasses
+{
+    public readonly record struct SixDigitInt
+    {
+        public int Value { get; }
+
+        public SixDigitInt(int value)
+        {
+            if (value < 0 || value > 999999)
+                throw new ArgumentOutOfRangeException(nameof(value),
+                    "Wert muss zwischen 0 und 999999 liegen.");
+
+            Value = value;
+        }
+
+        public override string ToString() => Value.ToString("D6");
+
+        public static implicit operator int(SixDigitInt v) => v.Value;
+    }
+}