Sum all data in array of objects into new array of objects

Question

I have an array of objects that looks like this:

var data = [{costOfAirtickets: 2500, costOfHotel: 1200},{costOfAirtickets: 1500, costOfHotel: 1000}]
         


        

Answer 1

My simplistic answer would be like;

var data = [{costOfAirtickets: 2500, costOfHotel: 1200},
            {costOfAirtickets: 1500, costOfHotel: 1000}],
    res  = data.reduce((p,c) => Object.entries(c).reduce((r,[k,v]) => (r[k]+=v, r), p));
console.log(res);

A note on usage of .reduce(): If the array items and the accumulated value is of same type you may consider not using an initial value as an accumulator and do your reducing with previous (p) and current (c) elements. The outer reduce in the above snippet is of this type. However the inner reduce takes an array of key (k) value (v) pair as [k,v] to return an object, hence an initial value (p) is essential.

The result is the accumulated value as an object. If you need it in an array then just put it in an array like [res].