Update implemented removeCurrency

CM2005 Object Oriented Programming/Topic 5/5.1.9/Wallet.cpp

@@ -24,6 +24,29 @@ void Wallet::insertCurrency(std::string type, double amount)
   currencies[type] = balance;
 }
 
+bool Wallet::removeCurrency(std::string type, double amount)
+{
+  double balance;
+  if(amount < 0)
+  {
+    return false;
+  }
+  if(currencies.count(type) == 0) // currency not in wallet
+  {
+    return false;
+  }
+  else // is there, do we have enough?
+  {
+    if(containsCurrency(type, amount))
+    {
+      currencies[type] -= amount;
+      return true;
+    }
+    else // didn't have enough
+      return false;
+  }
+}
+
 bool Wallet::containsCurrency(std::string type, double amount)
 {
   if(currencies.count(type) == 0) // not in wallet yet
@@ -44,4 +67,4 @@ std::string Wallet::toString()
     s += currency + " : " + std::to_string(amount) + "\n";
   }
   return s;
-}
+}