characters and loop through that to see if a guess is a repeat. You could use a sting for that too, but a string in SmileBasic is really just a special kind of character array.
Finally in guess the number you may want to save the guesses and print them out. That is easier to do if you save them in an array then if you have a bunch of guess_1 through guess_10 variables. You could just push and pop
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