Iterating through an array in Javascript to create a new array filled with objects

Question

Iterating through an array in Javascript to create a new array filled with objects

Is there a way to iterate through an array of strings and convert them into an array of objects based on their values?

For instance, if the array looks like this:

[a,a,a,b,b,c,d]

I aim to cycle through the array and create objects with key-value pairs that increment the values for each string:

[{a:1},{a:2},{a:3},{b:1},{b:2},{c:1},{d:1}]

Any suggestions on how to accomplish this task?

I've attempted mapping through the array, but I'm struggling with updating the value of the previous object (a:1 -> a:2).

javascript arrays loops object

Answer 1

Answer №1

When creating a map during the process of mapping, it is crucial to keep track of the frequency of each item by incrementing the count of the corresponding key with each iteration. One effective way to achieve this is by utilizing a Map:

const input = ['a','a','a','b','b','c','d'];
const map = new Map();
console.log(
  input.map(char => {
    const count = (map.get(char) || 0) + 1;
    map.set(char, count);
    return { [char]: count };
  })
)

Answer 2

When creating a map during the process of mapping, it is crucial to keep track of the frequency of each item by incrementing the count of the corresponding key with each iteration. One effective way to achieve this is by utilizing a Map:

const input = ['a','a','a','b','b','c','d'];
const map = new Map();
console.log(
  input.map(char => {
    const count = (map.get(char) || 0) + 1;
    map.set(char, count);
    return { [char]: count };
  })
)

Iterating through an array in Javascript to create a new array filled with objects

Answer №1

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