How to convert primitive array into object array with key and value?

[Brutal_Jazzy]

Sir i have added a new question which explains very well i am sorry for the disturbance please check this question out:

I have an array i want to push keys on each value and also want to count how many times they were repeated using aggregation

i have a document like this: { _id: 1 a: a b: b c: [ 1, 2, 3, 4, -4, -5, 6, 6 ] } now i want to use aggregate to make a new field "d: and in that field it will be an array of objects which will show all repeating values and how many they were repeat and if the value is negative like this should be result document. { _id: 1 a: a b: b c: [ 1, 2, 3, 4, -4, -5, 6, 6 ] d: [{value: 1, timeShown: 1 , type: positive}, {value: 2, timeShown: 1, type: positive}, {value: 3, timeShown: 1, type: po…