Add included the header file to the main file and both cpp files

CM2005 Object Oriented Programming/Topic 2/2.5.3/OrderBookEntry.h

@@ -0,0 +1,25 @@
+#include <string>
+
+enum class OrderBookType
+{
+  bid,
+  ask
+};
+
+class OrderBookEntry
+{
+  public:
+    OrderBookEntry
+    (
+      double price,
+      double amount,
+      std::string timestamp,
+      std::string product,
+      OrderBookType orderType
+    );
+    double price;
+    double amount;
+    std::string timestamp;
+    std::string product;
+    OrderBookType orderType;
+};