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Task/Caesar-cipher/Phix/caesar-cipher.phix

@@ -0,0 +1,19 @@
+sequence alpha_b = repeat(0,255)
+         alpha_b['A'..'Z'] = 'A'
+         alpha_b['a'..'z'] = 'a'
+
+function caesar(string s, integer key)
+integer ch, base
+    for i=1 to length(s) do
+        ch = s[i]
+        base = alpha_b[ch]
+        if base then
+            s[i] = base+remainder(ch-base+key,26)
+        end if
+    end for
+    return s
+end function
+string s = "One fine day in the middle of the night, two dead men got up to fight. \n"&
+           "Back to back they faced each other, drew their swords and shot each other. %^&*()[",
+       e = caesar(s,5),
+       r = caesar(e,26-5)  ?e ?r