Data commit

Task/Substitution-cipher/Ring/substitution-cipher.ring

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+# Project : Substitution Cipher
+
+plaintext = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+ciphertext = "ZEBRASCDFGHIJKLMNOPQTUVWXY"
+test = "flee at once. we are discovered!"
+encrypt = "SIAA ZQ LKBA. VA ZOA RFPBLUAOAR!"
+
+see "Plaintext : " + plaintext + nl
+see "Ciphertext : " + ciphertext + nl
+see "Test : " + test + nl
+see "Encoded : "
+encodetext = encode(test)
+see encodetext + nl
+see "Decoded : "
+decodetext = decode(encodetext)
+see decodetext + nl
+
+func encode(test)
+        str = ""
+        for n = 1 to len(test)
+              pos = substr(plaintext, upper(test[n]))
+              if test[n] = " "
+                 str = str + " "
+              elseif test[n] = "!"
+                 str = str + "!"
+              elseif test[n] = "."
+                 str = str + "."
+              else
+                 str = str + substr(ciphertext, pos, 1)
+              ok
+        next
+        return str
+
+func decode(test)
+        str = ""
+        for n = 1 to len(encodetext)
+              pos = substr(ciphertext, upper(encodetext[n]))
+              if test[n] = " "
+                 str = str + " "
+              elseif test[n] = "!"
+                 str = str + "!"
+              elseif test[n] = "."
+                 str = str + "."
+              else
+                 str = str + lower(substr(plaintext, pos, 1))
+              ok
+        next
+        return str