Q1: I'm declaring "Person friend;" and compiler says "Unexpected type name 
    "Person" encountered." 
Q2: How does one count the years if a person is born on February 29 on a leap 
    year?  
--------------------------------------------------------------------------------

Q1: I'm declaring "Person friend;" and compiler says "Unexpected type name 
    "Person" encountered." 

A1: "friend" is a reserved word.  Do NOT use as an identifier name.
--------------------------------------------------------------------------------

Q2: How does one count the years if a person is born on February 29 on a leap 
    year?  

A2: Just handle it as one year of living is one year of age.
Yes, it is too strange because their day of birth occurs once every 4 years.
But this is not the "Fountain of Youth" solution.
--------------------------------------------------------------------------------