Array.prototype.merge_Sort = function () {  
  if (this.length <= 1)   
  {  
    return this;  
  }  
  
  var half = parseInt(this.length / 2);  
  var left = this.slice(0, half).merge_Sort();  
  var right = this.slice(half,     this.length).merge_Sort();  
  var merge = function (left, right)   
  {  
  var arry = [];  
  while (left.length > 0 && right.length > 0)  
  {  
    arry.push((left[0] <= right[0]) ? left.shift() : right.shift());  
  }  
    return arry.concat(left).concat(right);  
  };  
  
  return merge(left, right);  
};  
  
var a = [34,7,23,32,5,62];  
console.log(a.merge_Sort());  