#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  string s, ans;
  int n, cnt = 0;
  cin >> n >> s;
  ans += s[0];
  for (int i = 1; i < s.length(); i++) {
    if (ans.length() % 2 == 0)
      ans += s[i];
    else {
      if (ans[ans.length() - 1] != s[i])
        ans += s[i];
      else
        cnt += 1;
    }
  }
  if (ans.length() % 2 == 1) cnt += 1;
  cout << cnt << "\n";
  if (ans.length() == 1)
    cout << "";
  else {
    if (ans.length() % 2 == 0)
      cout << ans;
    else
      for (int i = 0; i < ans.length() - 1; i++) cout << ans[i];
  }
  return 0;
}
