Route #1: 5 15 31 22 13 8
Route #2: 30 36 12 32 17 14 29 1
Route #3: 23 10 40 20 16 7
Route #4: 25 6 33 34 11 28
Route #5: 24 35 2 3 18 21 37 9
Route #6: 4 39 38 27 26 19
cost 829