#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, b[1000000010];
  cin >> n;
  long long a[n];
  if (n != 3 && n % 2 == 1) {
    cout << "No" << endl;
    return 0;
  }
  for (int i = 0; i < n; i++) {
    cin >> a[i];
    b[a[i]]++;
  }
  int count = 0;
  for (auto c : b) {
    count++;
  }
  if (count != 3) {
    cout << "No" << endl;
    return 0;
  }
  cout << "Yes" << endl;
}
