Are you sure there are no problems with the examples here?

Question

The fourth paragraph example, the final is 100

The fifth paragraph example, the result is 'I am a soldier, from the common people' instead of 'helping others is happy'

and so on, In addition, global $a defines a global variable. How can I call global variable $a elsewhere in the program? Is there no need to add any identifier to distinguish it?

Answer 1

unnecessary