问使用填充的Javascript数组混洗

EN

function one(array, mod){
    var modArray = [];
    for(var index in array){
        var item = array[index];
        var itemMod = item%3;
        if(itemMod === mod){
            modArray.push(item);
        }
    }
    return modArray();
}

function two(modArray){
    var sortedArray = // sort highest to lowest
    for(var index in sortedArray ){
        var item = array[index];
        if(index > 0 && item[index-1] === item[index]-3){

        }else{return false;}          
    }
    return sortedArray.length;
}

function main(array){
    var a1 = one(array, 0);
    var a2 = one(array, 1);
    var a3 = one(array, 2);

    var a1c = two(a1);
    var a2c = two(a2);
    var a3c = two(a3);

    return // if a1c is greatest then a1, if a2c greatest then a2 ... etc
}