updated regex to include -numbers

Calculations.java

             //return the array list
         //else return null'
         
-        Pattern pattern = Pattern.compile("\\s?\\.?\\d+\\.?(\\d+)?\\s?");
+        Pattern pattern = Pattern.compile("\\s?\\-?\\.?\\d+\\.?(\\d+)?\\s?");
         Matcher matcher = pattern.matcher(userInput);
         
         while(matcher.find()){
             String number = matcher.group().trim();
             Double deci = Double.valueOf(number);
+            System.out.println(deci);
             results.add(deci);
         }