https://people.sc.fsu.edu/~jburkardt/datasets/tsp/tsp.html

input15.txt 
solution : 1, 13, 2, 15, 9, 5, 7, 3, 12, 14, 10, 8, 6, 4, 11
optimal fitness : 291

input26.txt
solution : 1, 25, 24, 23, 26, 22, 21, 17, 18, 20, 19, 16, 11, 12, 13, 15, 14, 10, 9, 8, 7, 5, 6, 4, 3, 2, 1 
optimal fitness : 937