1 | 16. s1: traversal(the_graph) 17. s2: traversal(the_graph) 18. j:Vertices(the_graph).
((inl(j) s1)  L1-the_graph- > *j) & ((inl(j) s2)  nil-the_graph- > *j & L1-the_graph- > *j) 19. j: Vertices(the_graph) 20. (inl(j) s1) 21. L1-the_graph- > *j L1-the_graph- > *j e-the_graph- > *j | 1 step |
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2 | 16. s1: traversal(the_graph) 17. s2: traversal(the_graph) 18. j:Vertices(the_graph).
((inl(j) s1)  L1-the_graph- > *j) & ((inl(j) s2)  nil-the_graph- > *j & L1-the_graph- > *j) 19. j: Vertices(the_graph) 20. L1-the_graph- > *j e-the_graph- > *j L1-the_graph- > *j | 4 steps |
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3 | 16. s1: traversal(the_graph) 17. s2: traversal(the_graph) 18. j:Vertices(the_graph).
((inl(j) s1)  L1-the_graph- > *j) & ((inl(j) s2)  nil-the_graph- > *j & L1-the_graph- > *j) 19. j: Vertices(the_graph) 20. (inl(j) s2) 21. nil-the_graph- > *j & L1-the_graph- > *j L2@0-the_graph- > *j & (L1-the_graph- > *j e-the_graph- > *j) | 1 step |
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4 | 16. s1: traversal(the_graph) 17. s2: traversal(the_graph) 18. j:Vertices(the_graph).
((inl(j) s1)  L1-the_graph- > *j) & ((inl(j) s2)  nil-the_graph- > *j & L1-the_graph- > *j) 19. j: Vertices(the_graph) 20. L2@0-the_graph- > *j & (L1-the_graph- > *j e-the_graph- > *j) nil-the_graph- > *j & L1-the_graph- > *j | 4 steps |