RPNEVAL - Evaluate simple RPN expression - Problem

A couple of observations:

1. It handles leading spaces, but not trailing. Any trailing space causes it to output ERROR.
2. I have an input of three lines of RPN, and it gives four lines of output.

How many inputs we should get for this problem? There is no limit mentioned and the question seems something akward. Please resolve this problem

Knowing what is EOF and any searching engine are your best friends.
For exemple, you can search: "python read up to eof" For example: https://stackoverflow.com/questions/15599639/what-is-the-perfect-counterpart-in-python-for-while-not-eof2

PS
I use C++