var maxN = eval("Math.max(" + ary.toString() + ")");
var minN = eval("Math.min(" + ary.toString() + ")");

var maxN = eval("Math.max(" + ary.join() + ")");
var minN = eval("Math.min(" + ary.join() + ")");

ary.sort(function(a,b){return a-b;});
var minN = ary[0];
var maxN = ary[ary.length-1];

var maxN = ary[0];
var minN = ary[0];
for(var i=1;i<ary.length;i++){
  var cur = ary[i];
  cur>maxN ? maxN=cur : null;
  cur<minN ? minN=cur : null;
}

var maxN = Math.max.apply(null,ary);
var minN = Math.min.apply(null,ary);