Hackerrank: Sock Merchant Solution

1function sockMerchant(n, ar) {
2  const group = ar.reduce((acc, el) => {
3    if (acc[el]) {
4      acc[el] += 1
5    } else {
6      acc[el] = 1
7    }
8    return acc
9  }, {})
10  const values = Object.values(group)
11  return values.map(v => Math.floor(v / 2)).reduce((acc, el) => acc + el, 0)
12}