I want to know these things:-
STEP(8) = OBSERVATION : Observe the Do...Loop While(num2 <= 9) loop inside the 'Try' block.
CONCLUSION : It ensures that, there are not repeated digits in the key. Thus, note that, the key consists only of DIGITS no alphabets.
how can i find this that there is only digits no alphabets and even digits are not repeated.
STEP(14)= i am newbie so i don't know "how to " and "where is to" put getserial function.

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