include "inverse.mzn";
int: n;
array[1..n] of var 1..n: x; % sequence of numbers
array[1..n-1] of var 1..n-1: u; % sequence of differences
constraint forall(i in 1..n-1)(u[i] = abs(x[i+1] - x[i]));
array[1..n] of var 1..n: y; % position of each number
array[1..n-1] of var 1..n-1: v; % position of difference i
constraint inverse(x,y);
constraint inverse(u,v);
constraint abs(y[1] - y[n]) = 1 /\ v[n-1] = min(y[1], y[n]);
solve :: int_search(y, first_fail, indomain_min, complete)
satisfy;
output ["x = ",show(x),"\n"];