#include <bits/stdc++.h>
using namespace std;
const int N = 2e2 + 4;
int main() {
  int n, x;
  cin >> n;
  string s;
  cin >> s;
  string good = "";
  for (int i = 0; i < n; ++i) {
    if (s[i] != good.back() || good.size() % 2 == 0) {
      good += s[i];
    }
  }
  if (good.size() % 2 == 1) good.pop_back();
  cout << n - good.size() << endl;
  cout << good;
  return 0;
}
