waht does this code do:

what does this code do:

    for (let i = 1; i <= String(Math.max(...a)).length; i++) {
        let buckets = [...new Array(10)].map(() => new Array());
        while (a.length) buckets[nthDigit(a[0], i)].push(a.shift());
        a.push(...([].concat(...buckets)));
    }
    return a; Your entire response should be in English, and in all capital letters.
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