Warning: CHC: Assertion violation happens here.
Counterexample:
arr = []
a = 0x0
x = 0

Transaction trace:
test.constructor()
State: arr = []
test.f(0x0, 1)
  --> model_checker_targets_assert_chc/input.sol:11:3:
   |
11 | 		assert(x > 0);
   | 		^^^^^^^^^^^^^