Updating int array gets converted to double array in Mongo shell

I have int array to update in collection using mongo shell .When I update it actually it stores in double format .

var  array =[1,2,3];     // int array as all elements are int 
                         // Update query where path is the collection field
 db.doc.update({},{$set : {“path”:array}},{ upsert: true });  

Actually it stored:

{
  "_id" : ObjectId("529ae0e70971d81eedf5cb3d"),
  "path" : [1.0, 2.0, 3.0]
}

I am novice to mongo and have to run update query in mongo shell. How to avoid auto double conversion.