#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  cin >> n;
  string s;
  cin >> s;
  for (int i = 0; i < s.length() - 1; i++) {
    if (i % 2 == 0) {
      while (s[i] == s[i + 1]) {
        s.erase(s.begin() + i + 1);
      }
    }
  }
  if (s.length() % 2 == 0) {
    cout << n - s.length() << endl;
    cout << s;
  } else {
    s.erase(s.length() - 1);
    cout << n - s.length() << endl;
    cout << s;
  }
}
