practice

function mode(array)
{
    if(array.length == 0)
        return null;
    var modeMap = {};
    var maxEl = array[0], maxCount = 1;
    for(var i = 0; i < array.length; i++)
    {
        var el = array[i];
        if(modeMap[el] == null)
            modeMap[el] = 1;
        else
            modeMap[el]++;
        if(modeMap[el] > maxCount)
        {
            maxEl = el;
            maxCount = modeMap[el];
        }
    }

    var sortable = [];
    for (var key in modeMap) {
        sortable.push([key, modeMap[key]]);
    }

    sortable.sort(function(a, b) {
        return b[1] - a[1];
    });



    if (sortable[0][1] === sortable[1][1]) {
        return sortable[1][1]
    }

    return maxEl;
}
mode([34,31,34,77,82])