jens, you consider 2,8GHz celeron a fast computer?

and, if you run the code with the test cases you gave us and not your hidden private tests, it will surely finish in time.

now, if the rule does not allow excessive run-times, you should change the rule to say that.
as now the rule says "as long as the code finishes inside the phase's alloted time, it's ok"
and again, 3 days is lot less excessive than what the rule says is allowed.