#include <bits/stdc++.h>
using namespace std;
int ct = INT_MAX;
int main() {
  int t = 1;
  while (t--) {
    int n, ans = 0;
    string s;
    cin >> n >> s;
    string l = "";
    for (int i = 0; i < n; i += 2) {
      while (i < (n - 1) && s[i] == s[i + 1]) {
        ans++;
        i++;
      }
      if (i < n) l += s[i];
      if ((i + 1) < n) l += s[i + 1];
    }
    if (l.length() % 2 != 0) {
      ans++;
      l.pop_back();
    }
    cout << ans << endl;
    cout << l << endl;
  }
  return 0;
}
