Substring primes: Difference between revisions
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=={{header|Picat}}==
===Checking via substrings===
<lang Picat>% get all the substrings of a number
subs(N) = findall(S, (append(_Pre,S,_Post,N.to_string), S.len > 0) ).
go =>
Ps = [],
foreach(Prime in primes(500))
(foreach(N in subs(Prime) prime(N) end -> Ps := Ps ++ [Prime] ; true)
end,
println(Ps).</lang>
{{out}}
<pre>[2,3,5,7,23,37,53,73,373]</pre>
===Checking via predicate===
{{trans|AWK}}
Here we must use cut (<code>!</code>) to ensure that the test does not continue after a satisfied test. This is a "red cut" (i.e. removing it would change the logic of the program) and these should be avoided if possible.
<lang Picat>t(N,false) :-
not prime(N),!.
t(N,true) :-
N < 10,!.
t(N,false) :-
not prime(N mod 100), !.
t(N,false) :-
not prime(N mod 10),!.
t(N,false) :-
not prime(N // 10),!.
t(N,true) :-
N < 100,!.
t(N,false) :-
not prime(N // 100),!.
t(N,false) :-
not prime((N mod 100) // 10),!.
t(_N,true).
go2 =>
println(findall(N,(member(N,1..500),t(N,Status),Status==true))).</lang>
{{out}}
<pre>[2,3,5,7,23,37,53,73,373]</pre>
=={{header|Phix}}==
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