Warning: Function state mutability can be restricted to pure
 --> model_checker_show_proved_safe_true_all_engines/input.sol:4:5:
  |
4 |     function f(uint8 x) public {
  |     ^ (Relevant source part starts here and spans across multiple lines).

Info: CHC: Assertion violation check is safe!
 --> model_checker_show_proved_safe_true_all_engines/input.sol:5:9:
  |
5 |         assert(x >= 0);
  |         ^^^^^^^^^^^^^^

Info: CHC: Assertion violation check is safe!
 --> model_checker_show_proved_safe_true_all_engines/input.sol:6:9:
  |
6 |         assert(x < 1000);
  |         ^^^^^^^^^^^^^^^^
