[Solved] array return element based on number occurrence [closed]

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Adding an example code (the thing you’d already tried) is not only polite on StackOverflow, but also helps answering question about your problem – it’s easier to help with an example.

But, I’ll give it a try now:

const people = ['Mary', 'Paul', 'John', 'Lisa', 'Mary', 'Mary', 'Paul', 'Lisa'];

// counting the names & storing in an object
const countAppearance = ({
  arr
}) => {
  return arr.reduce((a, c) => {
    if (typeof a[c] === "undefined") a[c] = 0
    a[c]++
      return a
  }, {})
}

const ca = countAppearance({
  arr: people
})

// getting names as an array by count number
const getAppearanceByCount = ({
  obj,
  count
}) => {
  return Object.entries(obj).filter(([key, val]) => val <= count).reduce((a, c) => [...a, c[0]], [])
}

// getting names that appear twice
const countTwo = getAppearanceByCount({
  obj: ca,
  count: 2
})

console.log("two:", countTwo)

// getting names that appear three times
const countThree = getAppearanceByCount({
  obj: ca,
  count: 1
})

console.log("three:", countThree)

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solved array return element based on number occurrence [closed]