[рони]

cyber,
сравнение количества операций для преобразования и длины нового массива ...

function rand()
{  var l = Math.round(Math.random() * 100), a = [];
   for (var i=0; i<l; i++)  {a[i]=Math.round(Math.random() * 100)}
   return a
}

function compare_indexOf(fArr,arr) {

    var search = arr.slice(),
        insert = [],
        remove = [],
        replace = [];

    for(var i = 0, index; i < fArr.length; i++) {

        index = search.indexOf(fArr[i]);

                if(!~index) {

                        remove.push(i);
            continue;
        }

       i != index &&  replace.push({'old': i, 'new': index});

        delete search[index];

        };

    search.forEach(function (elem, i) {
        if(elem)
          insert.push(i);
    });

    return {
        'remove': remove,
        'insert': insert,
        'replace': replace
    }

}
function compare(f, d) {
    var e = {
        relocation: [],
        insert: [],
        length: d.length
    }, c = d + ", " + f ,
        b = f.slice();
    if (c = c.match(/([^,]\S*[^,])(?=,[\s\S]*\s[\s\S]*\1)/g)) {
        c.reverse();
        for (var a = 0; a < c.length; a++) {
            var g = ("" + b).slice(0, ("" + b).lastIndexOf(c[a]) + 1).split(",").length - 1,
                h = c[a].split(",").length,
                k = b.splice(g, h);
            e.relocation.push([g, h]);
            b = k.concat(b)
        }
    }
    for (a = 0; a < d.length; a++) d[a] != b[a] && (b.splice(a, 0, d[a]), e.insert.push([a, d[a]]));
    return e
};
var oldArray = rand();
var newArray = rand();
var time_indexOf = new Date();
var changes = compare_indexOf(oldArray, newArray);
time_indexOf = (new Date()).getTime() - time_indexOf.getTime()
var len_indexOf = changes.remove.length + changes.insert.length + changes.replace.length;
var time = new Date();
var changes = compare(oldArray, newArray);
time = (new Date()).getTime() - time.getTime()
var len = changes.relocation.length + changes.insert.length + 1;
alert('len_indexOf : ' + len_indexOf + ' time: ' + time_indexOf + '\nlen: ' + len + ' time: ' + time + '\nlength : ' + newArray.length);