#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  string s;
  getline(cin, s);
  getline(cin, s);
  int che = 0;
  vector<int> a(n, 1);
  int i = 0;
  int y = 1;
  while (i < n) {
    if (y < n && s[i] == s[y] && che == 0) {
      a[y] = 0;
      ++y;
    } else {
      i = y + 1;
      y = i + 1;
    }
  }
  string an, ans;
  for (i = 0; i < n; ++i)
    if (a[i]) an += s[i];
  if ((an.length() % 2) == 1) {
    for (i = 0; i < an.length() - 1; ++i) ans += an[i];
  } else
    ans = an;
  cout << n - ans.length() << "\n";
  cout << ans;
  return 0;
}
