Thread: ArrayList assistance

Goal is to get user input and sum together. I've tried it different ways. This is the one with the least amount of problems.

Exception in thread "main" java.lang.RuntimeException: Uncompilable source code - Erroneous sym type: java.lang.Integer.parseInt

        ArrayList<Integer> leftCU = new ArrayList<>();
        {
            System.out.println("Please enter one at a time the number of CU's for each class that is left to complete. Enter Q when done.");
            leftCU.add(in.nextInt());
            while (in.hasNextInt()){
                leftCU.add(in.nextInt());
            }
 
         int sum= 0;
        for(int i=0; i < leftCU.size(); i++){
            sum = sum + Integer.parseInt(leftCU.get(i));   
                        }
        }

The error I get is for the line:

sum = sum + Integer.parseInt(leftCU.get(i));

leftCu.get(i) is highlighted with an error of: incompatible types: Integer cannot be converted into a String.

I don't see how I'm converting it into a string though. I want everything to stay an Integer.