1 | 5. i: Vertices(the_graph) 6. (i nil) (inl(i) nil) (inl(i) s) (inr(i) s) | 1 step |
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2 | l_disjoint(Vertices(the_graph)+Vertices(the_graph);nil;s) | 1 step |
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3 | no_repeats(Vertices(the_graph)+Vertices(the_graph);nil) | 1 step |
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4 | paren(Vertices(the_graph);nil) | 1 step |