include xpllib; \for StrLen, Print
char Key;

func Index(S, C);
char S, C, I;
[for I:= 0 to StrLen(S)-1 do
    if S(I) = C then return I;
return -1;
];

func Encode(S);
char S, I;
[for I:= 0 to StrLen(S)-1 do
    S(I):= Key(S(I)-32);
return S;
];

func Decode(S);
char S, I;
[for I:= 0 to StrLen(S)-1 do
    S(I):= Index(Key, S(I)) + 32;
return S;
];

char S, Enc;
[Key:= "]kYV}(!7P$n5_0i R:?jOWtF/=-pe'AD&@r6%ZXs^"v*N[#wSl9zq2^^+g;LoB`aGh{3.HIu4fbK)mU8|dMET><,Qc\C1yxJ";
S:= "The quick brown fox jumps over the lazy dog, who barks VERY loudly!";
Enc:= Encode(S);
Print("Encoded: %s\n", Enc);
Print("Decoded: %s\n", Decode(Enc));
]