Please take a look at: 4021643 and 6576225. They are exactly the same but one runs in 2s the other in 0.1s. My own submission also go TLE 130759328 while in my computer it runs in 0.188s

$time ./block_towers
real	0m0.188s
user	0m0.132s
sys	0m0.036s

Whats going on? I think that would be a good idea to improve FPC version from 3.0.4 to 3.2.0;

Thanks.