* Original Eccles & Toad solution (slightly modified)
 * Mark Byers reduced it to 187 bytes
 * Gordon McCreight reduced it to 186 bytes
 * Pablo Carbonell reduced it to 181 bytes
 * Simon Stroh changed @A=split//,<> to $/=\1;@A=<> to reduce the program to 179 bytes
 * Mitsuru Kariya changed @A[map{ ... }]  to map@A[ ... ] to reduce the program to 178 bytes
 * Ton Hospel shortened the program to 121 bytes