solves string/snake cube puzzles
One common 4x4x4 example:
$ go run scp.go 4 2 4 2 2 2 2 3 2 2 2 2 2 3 2 4 2 3 3 4 2 3 2 2 2 2 2 2 2 2 2 4 2 4 2 4 4 4 3
snake segment lengths: [4 2 4 2 2 2 2 3 2 2 2 2 2 3 2 4 2 3 3 4 2 3 2 2 2 2 2 2 2 2 2 4 2 4 2 4 4 4 3]
&{[true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true true] 4 4 4}
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4*+X -> 2*-Y -> 4*-X -> 2*+Z -> 2*+Y -> 2*+X -> 2*-Y -> 3*+X -> 2*+Y -> 2*-X -> 2*+Y -> 2*-X -> 2*-Z -> 3*+X -> 2*+Y -> 4*-X -> 2*-Y -> 3*+Z -> 3*-Y -> 4*+X -> 2*+Y -> 3*-X -> 2*+Y -> 2*+Z -> 2*-Y -> 2*+X -> 2*+Y -> 2*-Z -> 2*+X -> 2*-Z -> 2*+Y -> 4*-X -> 2*+Z -> 4*+X -> 2*+Z -> 4*-X -> 4*-Y -> 4*+X -> 3*+Y -> done