#include <bits/stdc++.h>
using namespace std;
int main() {
  int n;
  while (cin >> n) {
    int sum = 0, ans = 0;
    string s, ss;
    cin >> s;
    for (int i = 0; i < n;) {
      if ((i + 1 - sum) & 1 && i < n - 1) {
        if (s[i] == s[i + 1]) {
          i++;
          sum++;
        } else {
          ss += s[i];
          i++;
        }
      } else if ((i + 1 - sum) % 2 == 0) {
        ss += s[i];
        i++;
      } else {
        sum++;
        break;
      }
    }
    cout << sum << endl << ss << endl;
  }
  return 0;
}
