| author | nipkow |
| Wed, 19 Apr 2000 12:59:38 +0200 | |
| changeset 8749 | 2665170f104a |
| child 9145 | 9f7b8de5bfaf |
| permissions | -rw-r--r-- |
| 8749 | 1 |
\begin{isabelle}%
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% |
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\begin{isamarkuptext}%
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\noindent |
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Define the datatype of binary trees% |
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\end{isamarkuptext}%
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\isacommand{datatype}~'a~tree~=~Tip~|~Node~{"}'a~tree{"}~'a~{"}'a~tree{"}%
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\begin{isamarkuptext}%
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\noindent |
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and a function \isa{mirror} that mirrors a binary tree
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by swapping subtrees (recursively). Prove% |
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\end{isamarkuptext}%
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\isacommand{lemma}~mirror\_mirror:~{"}mirror(mirror~t)~=~t{"}\end{isabelle}%
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