N'th: Difference between revisions

=={{header|Picat}}==

nth/3 is a built-in predicate in Picat, so let's call the function nth2/1 and onward.

* nth2/1: {{trans|Prolog}}

* nth3/1: Function based with explicit conditions in head.

* nth4/1: {{trans|Python}}

<lang Picat>go =>

Ranges = [ 0..25, 250..265, 1000..1025],

foreach(Range in Ranges) println([nth2(I) : I in Range])

end,

nl.

%

% Translation of Prolog version

%

nth2(N) = N.to_string() ++ Th =>

( tween(N) -> Th = "th"

; 1 = N mod 10 -> Th = "st"

; 2 = N mod 10 -> Th = "nd"

; 3 = N mod 10 -> Th = "rd"

; Th = "th" ).

tween(N) => Tween = N mod 100, between(11, 13, Tween).

%

% Using explicit conditions

%

nth3(N) = cc(N,"th"), tween(N) => true.

nth3(N) = cc(N,"st"), N mod 10 = 1 => true.

nth3(N) = cc(N,"nd"), N mod 10 = 2 => true.

nth3(N) = cc(N,"rd"), N mod 10 = 3 => true.

nth3(N) = cc(N,"th") => true.

% helper function

cc(N,Th) = N.to_string() ++ Th.

%

% Translation of the Python version

%

nth4(N) = Nth =>

Suffix = ["th","st","nd","rd","th","th","th","th","th","th"],

Nth = N.to_string() ++ cond((N mod 100 <= 10; N mod 100 > 20), Suffix[1 + N mod 10], "th").</lang>

{{out}}

<pre>[0th,1st,2nd,3rd,4th,5th,6th,7th,8th,9th,10th,11th,12th,13th,14th,15th,16th,17th,18th,19th,20th,21st,22nd,23rd,24th,25th]

[250th,251st,252nd,253rd,254th,255th,256th,257th,258th,259th,260th,261st,262nd,263rd,264th,265th]

[1000th,1001st,1002nd,1003rd,1004th,1005th,1006th,1007th,1008th,1009th,1010th,1011th,1012th,1013th,1014th,1015th,1016th,1017th,1018th,1019th,1020th,1021st,1022nd,1023rd,1024th,1025th]</pre>