Determine if a string has all unique characters: Difference between revisions

=={{header|F_Sharp|F#}}==

<lang fsharp>

// Determine if a string has all unique characters. Nigel Galloway: June 9th., 2020

let fN (n:string)=n.ToCharArray()|>Array.mapi(fun n g->(n,g))|>Array.groupBy(fun (_,n)->n)|>Array.filter(fun(_,n)->n.Length>1)

let allUnique n=match fN n with

g when g.Length=0->printfn "All charcters in <<<%s>>> (length %d) are unique" n n.Length

|g->Array.iter(fun(n,g)->printf "%A is repeated at positions" n; Array.iter(fun(n,_)->printf " %d" n)g;printf " ")g

printfn "in <<<%s>>> (length %d)" n n.Length

allUnique ""

allUnique "."

allUnique "abcABC"

allUnique "XYZ ZYX"

allUnique "1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ"

</lang>

{{out}}

<pre>

All charcters in <<<>>> (length 0) are unique

All charcters in <<<.>>> (length 1) are unique

All charcters in <<<abcABC>>> (length 6) are unique

'X' is repeated at positions 0 6 'Y' is repeated at positions 1 5 'Z' is repeated at positions 2 4 in <<<XYZ ZYX>>> (length 7)

'0' is repeated at positions 9 24 in <<<1234567890ABCDEFGHIJKLMN0PQRSTUVWXYZ>>> (length 36)

</pre>