131: Mainline 
 
What you have learned about parameters also applies to local variables:
 
- Local variables are available only inside the function in which they are 
declared.  Thus, the assignment of a local variable has no effect on other, 
identically named variables or parameters that appear in the definitions of 
other functions. 
  
- The values of a function's local variables are not available after that 
   function has returned. 
  
- When one function calls another, the values of the local 
   variables in the calling function are not available during the 
   execution of the called function.