int_lin_ne.fzn 330 Bytes
% RUNS ON flatzinc
% RUNS ON fzn_fd_canon
% RUNS ON fzn_fdlp_canon
% RUNS ON fzn_lazyfd_canon

var 0..3: x1 :: output_var;
var 3..5: x2 :: output_var;
var 0..10: x3 :: output_var;
constraint int_lin_ne([], [], 42);
constraint int_lin_ne([1, 2, 3], [1, 2, 3], 0);
constraint int_lin_ne([2, 3, -1], [x1, x2, x3], 0);
solve satisfy;