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Discussion on: Help? .map .reduce

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Replies for: For those reading this in the future : Budi answer is much faster to execute than the one i provided above. My approach is using functionnal js, no...

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khuongduybui profile image
Duy K. Bui •

we can do it purely functional too

const input = [
  {name: "test1", category: "Categoria1", price: 3},
  {name: "test2", category: "Categoria1", price: 13.6},
  {name: "test3", category: "Categoria2", price: 8},
  {name: "test4", category: "Categoria2", price: 8}
];
const map = input
  .map((item) => [item. category, item.price])
  .reduce((result, current) => {
    if (result[current[0]] === undefined) result[current[0]] = 0;
    result[current[0]] += result[current[1]];
    return result;
  }, {});
const output = Object.keys(result).map((key) => [key, result[key]])