How would one go about pushing the error literal :error: to a Stack in Java? I can't just push the String ":error:", as that is different. Can someone give me an example of as simple as possible a way to push the error literal :error: onto a stack? Thanks.

3.1.1 Pushing Integers to the Stack push num where num is an integer possibly with a'-'suggesting a negative value. Here, -0' should be regarded as '0. Entering this expression will simply push num onto the stack. For example, input stack pu If num is not an integer, only push the error literal (error:) onto the stack instead of pushing num. For example, input stack prnshrror: push 2.5 error: push -x5