if(letters >=5 && digits >=5)
            { 
                System.out.println("Great job! String is acceptable");
                System.exit(0);
            }
            
            //after use, letter and digit variables reset to 0 
            letters = 0; 
            digits = 0; 
        } //end a program within an if statement, which is nested with a while loop 
          //with the use of System.exit(0)
          //0 indicates successful termination 
          //any non-zero value indicates an unsuccessful termination