C:\test>perl -nlE"s[(.)(?=.*?\1)][]g;say length;"
1987
4
2013
4
2113
3
122398723456321467891356178653534
9
1111111111111111
1
121212121212121212121212
2

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In reply to Re: Golf for unique digits by BrowserUk
in thread Golf for unique digits by Cody Fendant

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