u can't javascript under pressure

function arraySum(i) {
    
    // i will be an array, containing integers, strings and/or arrays like itself.
    // Sum all the integers you find, anywhere in the nest of arrays.
    
    var sum = 0;
    for (j=0;j<i.length;j++)
    {
        if ( i[j].substring ) continue;
        if ( i[j].indexOf ) sum += arraySum(i[j]);
        else sum += i[j];
    }
    return sum;
}

Testing "arraySum([[1,2,3],4,5])"...
WRONG: Got 6 but expected 15. Try again!