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export function encode(input: string, key: string, alphabet: string[] = "abcdefghijklmnopqrstuvwxyz".split("")): string {    let keyIndex = 0;    return input.split("").map((character) => {        if (!alphabet.includes(character.toLocaleLowerCase())) return character;        const isUpperCase = character.toLocaleUpperCase() == character;
        const charIndex = alphabet.indexOf(character.toLocaleLowerCase())        const keyCharacterIndex = alphabet.indexOf(key[keyIndex % key.length].toLocaleLowerCase())
        const shiftedCharacter = alphabet[(charIndex + keyCharacterIndex) % alphabet.length];
        keyIndex++;        return isUpperCase ? shiftedCharacter.toLocaleUpperCase() : shiftedCharacter;    }).join("");}
export function decode(input: string, key: string, alphabet: string[] = "abcdefghijklmnopqrstuvwxyz".split("")): string {    let keyIndex = 0;    return input.split("").map((character) => {        if (!alphabet.includes(character.toLocaleLowerCase())) return character;        const isUpperCase = character.toLocaleUpperCase() == character;
        const charIndex = alphabet.indexOf(character.toLocaleLowerCase())        const keyCharacterIndex = alphabet.indexOf(key[keyIndex % key.length].toLocaleLowerCase())
        let absoluteIndex = (charIndex - keyCharacterIndex);        if (absoluteIndex < 0) absoluteIndex = absoluteIndex % alphabet.length + alphabet.length;        const shiftedCharacter = alphabet[absoluteIndex % alphabet.length];
        keyIndex++;        return isUpperCase ? shiftedCharacter.toLocaleUpperCase() : shiftedCharacter;    }).join("");}