Here is a set of basic questions producing integer or string outputs. Answer them and format the result precisely with the JSON instructions provided:

Question 0 (Question id: q_wYf6Rjz):
Your job is to return the last character of a string as a string. For example, the last char of "hello" is "o". Return the last character of the following string: "problems"

Question 1 (Question id: q_42Saq):
Calculate 3 + -1 * -4.



Return a JSON with each question id as a key.

For every question id, supply an object whose 'answer' field stores the solution.
For even integers, nest 'half_answer' and 'double_answer' inside an additional 'additional_answer_info' field in the answer object.
If the response to a question is a string, add a 'first_char' field containing its first character.

Now provide the result JSON using the described format.

{"ground_truth": {"q_wYf6Rjz": {"answer": "s", "first_char": "s"}, "q_42Saq": {"answer": 7}}}