:tt.pl
Enter no of days older (1-90):  a
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Enter no of days older (1-90):  !
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Enter no of days older (1-90):  333
Invalid input, please try again
Enter no of days older (1-90):  99
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Enter no of days older (1-90):  07
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Enter no of days older (1-90):  9
You entered 9 days

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