Solving a Puzzle Using Picat

Source

Arrange the numbers 1-32, inclusive, in a circle such that the sum of any two adjacent numbers in the circular chain is a perfect square

Picat is a programming language for solving constraint problems, logic problems etc.
It's quite fast too compared to python z3 solver.
So, here's one way to solve the circle problem in picat
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main => go.

go =>

   % decision variables
   N = 32,
   Xs = new_list(N),

   % given constraints
   Xs :: 1..N,
   Sq = [I**2 : I in 2..7],

   % fix one number, to avoid rotation
   Xs[1] #= 1,
   foreach (I in 1..N-1),
       sum([(Xs[I+1]+Xs[I]) #= Sq[J] : J in 1..Sq.length]) #= 1,
   end,
   sum([(Xs[N]+Xs[1]) #= Sq[J] : J in 1..Sq.length]) #= 1,
   all_different(Xs),

   % solve and print
   Res = solve_all(Xs),

   foreach (R in Res),
      println(R),
   end,
   nl.

References:

  1. Picat Page
  2. HakanK's page on Picat