#include <bits/stdc++.h>
using namespace std;
long long int power(long long int a, long long int b) {
  long long int result = 1;
  while (b > 0) {
    int lastbit = (b & 1);
    if (lastbit) {
      result = (result * a) % 1000000007;
    }
    a = (a * a) % 1000000007;
    b = b >> 1;
  }
  return result % 1000000007;
}
long long int gcd(long long int a, long long int b) {
  if (b == 0) return a;
  return gcd(b, a % b);
}
vector<int> SieveOfEratosthenes(int n) {
  bool prime[n + 1];
  memset(prime, true, sizeof(prime));
  for (int p = 2; p * p <= n; p++) {
    if (prime[p] == true) {
      for (int i = p * p; i <= n; i += p) prime[i] = false;
    }
  }
  vector<int> v;
  v.push_back(0);
  for (int p = 2; p <= n; p++)
    if (prime[p]) v.push_back(p);
  return v;
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int n;
  cin >> n;
  string s;
  cin >> s;
  char a[n];
  for (int i = 0; i < n; i++) {
    a[i] = s[i];
  }
  for (int i = 0; i < n; i++) {
    int j;
    for (j = i + 1; j < n; j++) {
      if (s[i] != s[j]) {
        break;
      } else {
        a[j] = ' ';
      }
    }
    i = j;
  }
  vector<char> v;
  for (int i = 0; i < n; i++) {
    if (a[i] != ' ') {
      v.push_back(a[i]);
    }
  }
  if (v.size() % 2) {
    cout << n - v.size() + 1 << endl;
    for (int i = 0; i < (v.size() - 1); i++) {
      cout << v[i];
    }
    if ((v.size() - 1) == 0) {
      cout << " ";
    }
    return 0;
  }
  cout << n - v.size() << endl;
  for (int i = 0; i < v.size(); i++) {
    cout << v[i];
  }
  if (v.size() == 0) {
    cout << " ";
  }
  return 0;
}
