test.js

var indexFinder = function( maxItem, maxNumber, optionalParam ){
    this.maxItem                = maxItem,
        this.maxNumber          = maxNumber,
        this.optionalParam      = optionalParam,
        this.myArray            = [],
        this.arrindexs          = [],
    this.tools                  = {
        randomNumber : function randomNumber( min, Max ){
            return Math.floor(( Math.random() * Max ) + min )
        },
        arrFilled : function( maxItem, random ){
            if( random ){
                return this.arrShufle( this.arrFilled( maxItem, false ) )
            }
            return Object.keys( new Array( maxItem - 1 ).fill( 0 ) );
        },
        arrShufle : function(arr){
            return arr.sort(function() {
                return .5 - Math.random();
            });
        },
        arrValues : function(arr){
            returnvar = [];
            var x  = 0;
            for(i in arr){
                returnvar[x] = arr[i];
                x++;
            }
            return returnvar;
        }
    },
    this.collectionResult = function(arr){
        var split       = 0;
        var arrLength   = arr.length;
        var x           = 0;

        for(i in arr){
            if(( arr[i] + arr[arrLength - x] ) > this.maxNumber ){
                split++;
            }
            x++;
        }
        return split;
    },
    this.canBeUsed = function(){
        var arr         = this.tools.arrFilled( Math.max( this.maxItem, this.maxNumber ), true );
        this.myArray    = arr.slice(0, this.maxItem).sort(function(a, b){return b-a});
        this.myArray    = this.tools.arrValues(this.myArray);
        console.log("sdsad");
        //alert( this.collectionResult( this.myArray ) );
    };
};


var a = new indexFinder(20, 100);
a.canBeUsed();