How does mongodb mapreduce page?

  mongodb, question 
{mapreduce:"topic",
 query:{'time':{'$gte':1443715200}},
 map:function(){emit({name:this.name},this.clickNum);  },
 reduce:function(clickNum,numbers){return Array.sum(numbers);  },
 out:{inline:1}});

After using the above code to query a total of 300 pieces of data, how to page the collection at this time, for example, 20 pieces per page

Out can be output to a set, and then query and paginate the set.