Solution for "Sales by Match" in Hackerrank

Sales by Match |JavaScript | Solution.js

const ar = [10, 20, 20, 10, 10, 30, 50, 10, 20];
const n = 9;

function sockMerchant(n, ar) {
  let count = 0;
   ar.sort((a, b) => a - b);
  for (let i = 0; i < ar.length; i++) {
    if (ar[i] === ar[i + 1]) {
      i++ 
      count++;
    }
  }
  console.log(count);
}
sockMerchant(n, ar);