Question about user input error

I have a simple piece of code that requires the input of a number. I want to prevent the user from accidentally enters a letter. I tried a while loop using intnan, but I'm stuck.

Answer 1

[John BG]

try converting all inputs with uint.

If the return value of any input character does not belong to uint64('0123456789') then reject it, show a message or whatever you want to do.

John

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