function solve (arr) {

  let arr2 = [];

  let obj = {};



  for (let el of arr) {

    let cur = el.split(', ');

    arr2.push(cur[1]);

  }


  arr2.forEach(i => obj[i] = (obj[i] || 0) + 1);


  for (let key in obj) {

   if (obj[key] > 1) {

    obj[key] -= 2;

   }

  }


  for (let key in obj) {

      if (obj[key] === 0) {

        delete obj[key];

      }

  }


  // console.log(obj);

  arr2 = [];


  for (let key in obj) {

    arr2.push(key);

  }


  arr2.sort((a, b) => a.slice(2, 6) - b.slice(2, 6));


  if (arr2.length > 0) {

  for (let el of arr2) {

  console.log(el);

  }

} else {

  console.log(`Parking Lot is Empty`);

}



}