Return The Smallest Possible Join From Array Javascript

I have this code which works good for this array: ['45', '30', '50', '1']. function penalty(a_list) { return a_list.sort((a, b) => a - b).join(''); } for example: given that

Solution 1:

You could take the concatinated values of a and b and the value of b and a and take the delta of it for sorting, which reflects the sort order of the two string for a smaller value for later joining.

If integers are supplied, then the values need to be converted to string in the sort callback.

functionsort(a, b) {
    return (a + b) - (b + a);
}

console.log([['45', '30', '50', '1'], ['32', '3']].map(a => a.sort(sort).join('')));

For a stable sort, you could move smaller values to top (which does not affect the later joined string). This sorts '3' before '33'.

functionsort(a, b) {
    return (a + b) - (b + a) || a - b;
}

console.log([['45', '30', '50', '1'], ['32', '3']].map(a => a.sort(sort).join('')));