let arr1Length = +gets();
let arr1 = gets()
  .split(" ")
  .sort((a, b) => a - b);

let arr2Length = +gets();
let arr2 = gets()
  .split(" ")
  .sort((a, b) => a - b);

let checkArr1 = noDuplicates(arr1);

let checkArr2 = noDuplicates(arr2);
// console.log(checkArr1, checkArr2);

let sameNumbers = [];
let differentNumbers = [];

for (let i = 0; i < checkArr1.length; i++) {
  let element = checkArr1[i];
  if (checkArr2.includes(element)) {
    sameNumbers.push(element);
  } else {
    differentNumbers.push(element);
  }
}

if (differentNumbers.length === 0) {
  let result = sameNumbers.length;
  print(result);
} else {
    let result2 = differentNumbers.join(" ")
  print(result2);
}

function noDuplicates(arr) {
  let noDuplicatesArray = [];
  let previous = null;

  for (let i = 0; i < arr.length; i++) {
    let element = arr[i];
    if (previous === null) {
      noDuplicatesArray.push(element);
      previous = element;
      continue;
    }
    if (element === previous) {
      continue;
    }
    noDuplicatesArray.push(element);
    previous = element;
  }

  return noDuplicatesArray;
}