31 lines
746 B
Plaintext
31 lines
746 B
Plaintext
comment
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Return the rot13 transformation of s, preserving case and
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passing non-alphabetic characters without change
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end
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function rot13(s = string) = string
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var i, k = integer
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var ch = char
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var normal, rotated = string
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normal = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
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rotated = "NOPQRSTUVWXYZABCDEFGHIJKLMnopqrstuvwxyzabcdefghijklm"
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for i = 1 to len(s)
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ch = mid(s,i,1)
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k = instr(1,normal,ch)
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if k <> 0 then ch = mid(rotated,k,1)
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mid(s,i,1) = ch
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next i
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end = s
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rem - exercise the function
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var plain, encoded = string
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plain = "The quick brown fox jumps over the lazy dog."
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encoded = rot13(plain)
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print "Plain text: "; plain
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print "Encoded : "; encoded
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print "Decoded : "; rot13(encoded)
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end
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