18 lines
501 B
Forth
18 lines
501 B
Forth
# rosetta|is-palindrome
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A palindrome is a phrase which reads the same backward and forward.
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Write a function or program that checks whether a given sequence of
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characters (or, if you prefer, bytes) is a palindrome.
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In Retro this is fairly easy. We can use `s:hash` to identify a unique
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string. So make a copy, take he hash, reverse the copy, get its hash,
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and compare them.
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~~~
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:s:palindrome? (s-f)
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dup s:hash [ s:reverse s:hash ] dip eq? ;
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'ingirumimusnocteetconsumimurigni s:palindrome?
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~~~
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