#include <bits/stdc++.h>
const int maxn = 1e5 + 5;
using namespace std;
char str[2 * maxn];
int main() {
  int n;
  cin >> n;
  scanf("%s", str + 1);
  int sum = 1;
  char ss = str[1];
  queue<char> q;
  q.push(ss);
  for (int t = 2; t <= n; t++) {
    if (sum % 2 == 1 && str[t] == ss) {
      continue;
    }
    sum++;
    ss = str[t];
    q.push(str[t]);
  }
  if (sum % 2 == 1) {
    sum--;
  }
  printf("%d\n", n - sum);
  int cnt = 0;
  while (!q.empty()) {
    if (cnt == sum) {
      break;
    }
    cnt++;
    printf("%c", q.front());
    q.pop();
  }
  printf("\n");
  return 0;
}
