Mirror Words JS Fundamentals

function mirrorWords(arr) {
    let pattern = /([@#])(?<group>(?<word1>[a-zA-Z]{3,})\1\1(?<word2>[a-zA-Z]{3,}))\1/g;
    let pairs = [];
    let mirrorWords = [];

    while ((validPattern = pattern.exec(arr)) !== null) {
        let wordPairs = validPattern.groups['group'];
        pairs.push(wordPairs);
        let wordOne = validPattern.groups['word1'];
        let wordTwo = validPattern.groups['word2'];
        let reversed = '';
        for (let i = wordTwo.length - 1; i >= 0; i--) {
            reversed += wordTwo[i];
        }
        if (wordOne === reversed) {
            mirrorWords.push(`${wordOne} <=> ${wordTwo}`);
        }
    }
    pairs.join(' ');

    if (pairs.length > 0) {
    console.log(`${pairs.length} word pairs found!`);
    } else {
        console.log("No word pairs found!");
    }

    if (mirrorWords.length === 0) {
        console.log("No mirror words!");
    } else {
        console.log(`The mirror words are:\n${mirrorWords.join(', ')}`);
    }
}