#include <bits/stdc++.h>
using namespace std;
class BigInteger {
 public:
  BigInteger() { _data.push_back(0); }
  BigInteger(long long x) {
    while (x) {
      _data.push_back(x % _base);
      x /= _base;
    }
    if (_data.empty()) _data.push_back(0);
  }
  BigInteger(unsigned long long x) {
    while (x) {
      _data.push_back(x % _base);
      x /= _base;
    }
    if (_data.empty()) _data.push_back(0);
  }
  BigInteger(int x) : BigInteger((long long)x) {}
  BigInteger(unsigned int x) : BigInteger((unsigned long long)x) {}
  BigInteger(short x) : BigInteger((long long)x) {}
  BigInteger(unsigned short x) : BigInteger((unsigned long long)x) {}
  BigInteger(char x) : BigInteger((long long)x) {}
  BigInteger(unsigned char x) : BigInteger((unsigned long long)x) {}
  BigInteger(std::string &s) {
    for (int i = (int)s.size(); i > 0; i -= 9)
      if (i < 9)
        _data.push_back(atoi(s.substr(0, i).data()));
      else
        _data.push_back(atoi(s.substr(i - 9, 9).data()));
    while (_data.size() > 1 && _data.back() == 0) _data.pop_back();
  }
  BigInteger(const char *s) {
    std::string d = s;
    for (int i = (int)d.size(); i > 0; i -= 9)
      if (i < 9)
        _data.push_back(atoi(d.substr(0, i).data()));
      else
        _data.push_back(atoi(d.substr(i - 9, 9).data()));
    while (_data.size() > 1 && _data.back() == 0) _data.pop_back();
  }
  BigInteger(const BigInteger &b) {
    _data.resize(b._data.size());
    std::copy(b._data.begin(), b._data.end(), _data.begin());
  }
  void ToString(char *s) const {
    sprintf(s, "%d", _data.empty() ? 0 : _data.back());
    for (int i = (int)_data.size() - 2; i >= 0; i--)
      sprintf(s, "%s%09d", s, _data[i]);
  }
  std::string ToString() const {
    char *buff = (char *)malloc(20);
    sprintf(buff, "%d", _data.empty() ? 0 : _data.back());
    std::string res = buff;
    for (int i = (int)_data.size() - 2; i >= 0; i--) {
      sprintf(buff, "%09d", _data[i]);
      res += buff;
    }
    free(buff);
    return res;
  }
  friend const BigInteger operator+(BigInteger &i);
  friend const BigInteger &operator++(BigInteger &i);
  friend const BigInteger &operator--(BigInteger &i);
  friend const BigInteger operator++(BigInteger &i, int);
  friend const BigInteger operator--(BigInteger &i, int);
  friend const BigInteger operator+(const BigInteger &c, const BigInteger &b);
  friend const BigInteger operator-(const BigInteger &c, const BigInteger &b);
  friend const BigInteger operator*(const BigInteger &a, const BigInteger &b);
  friend const BigInteger operator/(const BigInteger &a, const BigInteger &b);
  friend const BigInteger operator%(const BigInteger &a, const BigInteger &b);
  friend BigInteger &operator+=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator-=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator*=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator/=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator%=(BigInteger &a, const BigInteger &b);
  friend bool operator==(const BigInteger &a, const BigInteger &b);
  friend bool operator<=(const BigInteger &a, const BigInteger &b);
  friend bool operator>=(const BigInteger &a, const BigInteger &b);
  friend bool operator<(const BigInteger &a, const BigInteger &b);
  friend bool operator>(const BigInteger &a, const BigInteger &b);
  friend bool operator!=(const BigInteger &a, const BigInteger &b);
  friend std::istream &operator>>(std::istream &is, BigInteger &i) {
    std::string s;
    is >> s;
    i = BigInteger(s);
    return is;
  }
  friend std::ostream &operator<<(std::ostream &os, const BigInteger &i) {
    os << i.ToString();
    return os;
  }

 private:
  static const int _base = 1000 * 1000 * 1000;
  std::vector<int> _data;
  int _cmp(const BigInteger &a, const BigInteger &b) const {
    if (a._data.size() > b._data.size()) return 1;
    if (a._data.size() < b._data.size()) return -1;
    for (int i = (int)a._data.size() - 1; i >= 0; i--) {
      if (a._data[i] > b._data[i]) return 1;
      if (a._data[i] < b._data[i]) return -1;
    }
    return 0;
  }
  BigInteger _div_short(const BigInteger &c, int b, int &mod) const {
    mod = 0;
    BigInteger a = c;
    for (int i = (int)a._data.size() - 1; i >= 0; i--) {
      long long cur = a._data[i] + mod * 1ll * BigInteger::_base;
      a._data[i] = int(cur / b);
      mod = int(cur % b);
    }
    while (a._data.size() > 1 && a._data.back() == 0) a._data.pop_back();
    return a;
  }
  bool _is_zero() const { return _data.size() == 1 && _data[0] == 0; }
};
const BigInteger operator+(const BigInteger &i) { return BigInteger(i); }
const BigInteger &operator++(BigInteger &i) {
  int j = 0;
  i._data[0]++;
  while (i._data[j] >= BigInteger::_base) {
    if (j == (int)i._data.size() - 1)
      i._data.push_back(1);
    else
      i._data[j + 1]++;
    i._data[j] -= BigInteger::_base;
    j++;
  }
  return i;
}
const BigInteger operator++(BigInteger &i, int) {
  BigInteger old = BigInteger(i);
  int j = 0;
  i._data[0]++;
  while (i._data[j] >= BigInteger::_base) {
    if (j == (int)i._data.size() - 1)
      i._data.push_back(1);
    else
      i._data[j + 1]++;
    i._data[j] -= BigInteger::_base;
    j++;
  }
  return old;
}
const BigInteger &operator--(BigInteger &i) {
  if (!i._is_zero()) i = i - 1;
  return i;
}
const BigInteger operator--(BigInteger &i, int) {
  BigInteger old = BigInteger(i);
  if (!i._is_zero()) i = i - 1;
  return old;
}
const BigInteger operator+(const BigInteger &c, const BigInteger &b) {
  BigInteger a = c;
  int carry = 0;
  for (size_t i = 0; i < std::max(a._data.size(), b._data.size()) || carry;
       i++) {
    if (i == a._data.size()) a._data.push_back(0);
    a._data[i] += carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] >= BigInteger::_base;
    if (carry) a._data[i] -= BigInteger::_base;
  }
  return a;
}
const BigInteger operator-(const BigInteger &c, const BigInteger &b) {
  if (c < b)
    throw std::invalid_argument("a - b, a must b greater or equal zero");
  BigInteger a = c;
  int carry = 0;
  for (size_t i = 0; i < b._data.size() || carry; i++) {
    a._data[i] -= carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] < 0;
    if (carry) a._data[i] += BigInteger::_base;
  }
  while (a._data.size() > 1 && a._data.back() == 0) a._data.pop_back();
  return a;
}
const BigInteger operator*(const BigInteger &a, const BigInteger &b) {
  BigInteger c;
  c._data.resize(a._data.size() + b._data.size());
  for (size_t i = 0; i < a._data.size(); i++)
    for (int j = 0, carry = 0; j < (int)b._data.size() || carry; j++) {
      long long cur =
          c._data[i + j] +
          a._data[i] * 1ll * (j < (int)b._data.size() ? b._data[j] : 0) + carry;
      c._data[i + j] = int(cur % BigInteger::_base);
      carry = int(cur / BigInteger::_base);
    }
  while (c._data.size() > 1 && c._data.back() == 0) c._data.pop_back();
  return c;
}
const BigInteger operator/(const BigInteger &a, const BigInteger &b) {
  if (b._is_zero()) throw std::invalid_argument("division by zero");
  BigInteger l = 0, r = a + 1, m;
  int t;
  while (r - l > 1) {
    m = a._div_short(r + l, 2, t);
    if (b * m <= a)
      l = m;
    else
      r = m;
  }
  return l;
}
const BigInteger operator%(const BigInteger &a, const BigInteger &b) {
  if (b._is_zero()) throw std::invalid_argument("division by zero");
  BigInteger l = 0, r = a + 1, m;
  int t;
  while (r - l > 1) {
    m = a._div_short(r + l, 2, t);
    if (b * m <= a)
      l = m;
    else
      r = m;
  }
  return a - b * l;
}
BigInteger &operator+=(BigInteger &a, const BigInteger &b) {
  int carry = 0;
  for (size_t i = 0; i < std::max(a._data.size(), b._data.size()) || carry;
       i++) {
    if (i == a._data.size()) a._data.push_back(0);
    a._data[i] += carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] >= BigInteger::_base;
    if (carry) a._data[i] -= BigInteger::_base;
  }
  return a;
}
BigInteger &operator-=(BigInteger &a, const BigInteger &b) {
  int carry = 0;
  for (size_t i = 0; i < b._data.size() || carry; i++) {
    a._data[i] -= carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] < 0;
    if (carry) a._data[i] += BigInteger::_base;
  }
  while (a._data.size() > 1 && a._data.back() == 0) a._data.pop_back();
  return a;
}
BigInteger &operator*=(BigInteger &a, const BigInteger &b) {
  a = a * b;
  return a;
}
BigInteger &operator/=(BigInteger &a, const BigInteger &b) {
  a = a / b;
  return a;
}
BigInteger &operator%=(BigInteger &a, const BigInteger &b) {
  a = a % b;
  return a;
}
bool operator==(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) == 0;
}
bool operator<=(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) <= 0;
}
bool operator>=(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) >= 0;
}
bool operator<(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) < 0;
}
bool operator>(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) > 0;
}
bool operator!=(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) != 0;
}
BigInteger binpow(BigInteger a, BigInteger n) {
  if (n == 0) return 1;
  if (n % 2 == 1)
    return binpow(a, n - 1) * a;
  else {
    BigInteger b = binpow(a, n / 2);
    return b * b;
  }
}
BigInteger gcd(BigInteger a, BigInteger b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
long long int gcd(long long int a, long long int b) {
  return b ? gcd(b, a % b) : a;
}
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
struct element {
  int x;
  element *Next;
};
class List {
  element *Head;

 public:
  List() { Head = NULL; }
  ~List();
  void Add(int x);
  void Show();
  void Delete();
  void Sort();
};
List::~List() {
  while (Head != NULL) {
    element *temp = Head->Next;
    delete Head;
    Head = temp;
  }
}
void List::Add(int x) {
  element *temp = new element;
  temp->x = x;
  temp->Next = Head;
  Head = temp;
}
void List::Show() {
  element *temp = Head;
  while (temp != NULL) {
    cout << temp->x << " ";
    temp = temp->Next;
  }
}
void List::Delete() {
  int k;
  cin >> k;
  element *temp = Head;
  element *prev = 0;
  while (temp) {
    element *next = temp->Next;
    if (temp->x == k) {
      if (prev) prev->Next = next;
      delete temp;
    } else {
      prev = temp;
    }
    temp = next;
  }
}
void List::Sort() {
  element *temp = Head;
  while (temp->Next) {
    if (temp->x > temp->Next->x) {
      swap(temp->x, temp->Next->x);
      temp = temp->Next;
      Sort();
    } else
      temp = temp->Next;
  }
}
int main() {
  int n;
  cin >> n;
  vector<char> a, b;
  char x;
  cin >> x;
  a.push_back(x);
  for (int i = 1; i < n; i++) {
    cin >> x;
    if (a.size() % 2 == 0)
      a.push_back(x);
    else if (x != a[a.size() - 1])
      a.push_back(x);
    if (b.size() == 0 || b.size() % 2 == 0)
      b.push_back(x);
    else if (x != b[b.size() - 1])
      b.push_back(x);
  }
  int maxi = max(a.size(), b.size());
  if (maxi % 2 == 1) maxi--;
  cout << n - maxi << endl;
  if (a.size() > b.size()) {
    int n = a.size();
    if (a.size() % 2 == 1) n--;
    for (int i = 0; i < n; i++) cout << a[i];
  } else {
    int n = b.size();
    if (b.size() % 2 == 1) n--;
    for (int i = 0; i < n; i++) cout << b[i];
  }
}

### Prompt

Please formulate a cpp solution to the following problem:

Let's call (yet again) a string good if its length is even, and every character in odd position of this string is different from the next character (the first character is different from the second, the third is different from the fourth, and so on). For example, the strings good, string and xyyx are good strings, and the strings bad, aa and aabc are not good. Note that the empty string is considered good.

You are given a string s, you have to delete minimum number of characters from this string so that it becomes good.

Input

The first line contains one integer n (1 ≤ n ≤ 2 ⋅ 10^5) — the number of characters in s.

The second line contains the string s, consisting of exactly n lowercase Latin letters.

Output

In the first line, print one integer k (0 ≤ k ≤ n) — the minimum number of characters you have to delete from s to make it good.

In the second line, print the resulting string s. If it is empty, you may leave the second line blank, or not print it at all.

Examples

Input


4
good


Output


0
good


Input


4
aabc


Output


2
ab


Input


3
aaa


Output


3

### Response

```cpp
#include <bits/stdc++.h>
using namespace std;
class BigInteger {
 public:
  BigInteger() { _data.push_back(0); }
  BigInteger(long long x) {
    while (x) {
      _data.push_back(x % _base);
      x /= _base;
    }
    if (_data.empty()) _data.push_back(0);
  }
  BigInteger(unsigned long long x) {
    while (x) {
      _data.push_back(x % _base);
      x /= _base;
    }
    if (_data.empty()) _data.push_back(0);
  }
  BigInteger(int x) : BigInteger((long long)x) {}
  BigInteger(unsigned int x) : BigInteger((unsigned long long)x) {}
  BigInteger(short x) : BigInteger((long long)x) {}
  BigInteger(unsigned short x) : BigInteger((unsigned long long)x) {}
  BigInteger(char x) : BigInteger((long long)x) {}
  BigInteger(unsigned char x) : BigInteger((unsigned long long)x) {}
  BigInteger(std::string &s) {
    for (int i = (int)s.size(); i > 0; i -= 9)
      if (i < 9)
        _data.push_back(atoi(s.substr(0, i).data()));
      else
        _data.push_back(atoi(s.substr(i - 9, 9).data()));
    while (_data.size() > 1 && _data.back() == 0) _data.pop_back();
  }
  BigInteger(const char *s) {
    std::string d = s;
    for (int i = (int)d.size(); i > 0; i -= 9)
      if (i < 9)
        _data.push_back(atoi(d.substr(0, i).data()));
      else
        _data.push_back(atoi(d.substr(i - 9, 9).data()));
    while (_data.size() > 1 && _data.back() == 0) _data.pop_back();
  }
  BigInteger(const BigInteger &b) {
    _data.resize(b._data.size());
    std::copy(b._data.begin(), b._data.end(), _data.begin());
  }
  void ToString(char *s) const {
    sprintf(s, "%d", _data.empty() ? 0 : _data.back());
    for (int i = (int)_data.size() - 2; i >= 0; i--)
      sprintf(s, "%s%09d", s, _data[i]);
  }
  std::string ToString() const {
    char *buff = (char *)malloc(20);
    sprintf(buff, "%d", _data.empty() ? 0 : _data.back());
    std::string res = buff;
    for (int i = (int)_data.size() - 2; i >= 0; i--) {
      sprintf(buff, "%09d", _data[i]);
      res += buff;
    }
    free(buff);
    return res;
  }
  friend const BigInteger operator+(BigInteger &i);
  friend const BigInteger &operator++(BigInteger &i);
  friend const BigInteger &operator--(BigInteger &i);
  friend const BigInteger operator++(BigInteger &i, int);
  friend const BigInteger operator--(BigInteger &i, int);
  friend const BigInteger operator+(const BigInteger &c, const BigInteger &b);
  friend const BigInteger operator-(const BigInteger &c, const BigInteger &b);
  friend const BigInteger operator*(const BigInteger &a, const BigInteger &b);
  friend const BigInteger operator/(const BigInteger &a, const BigInteger &b);
  friend const BigInteger operator%(const BigInteger &a, const BigInteger &b);
  friend BigInteger &operator+=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator-=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator*=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator/=(BigInteger &a, const BigInteger &b);
  friend BigInteger &operator%=(BigInteger &a, const BigInteger &b);
  friend bool operator==(const BigInteger &a, const BigInteger &b);
  friend bool operator<=(const BigInteger &a, const BigInteger &b);
  friend bool operator>=(const BigInteger &a, const BigInteger &b);
  friend bool operator<(const BigInteger &a, const BigInteger &b);
  friend bool operator>(const BigInteger &a, const BigInteger &b);
  friend bool operator!=(const BigInteger &a, const BigInteger &b);
  friend std::istream &operator>>(std::istream &is, BigInteger &i) {
    std::string s;
    is >> s;
    i = BigInteger(s);
    return is;
  }
  friend std::ostream &operator<<(std::ostream &os, const BigInteger &i) {
    os << i.ToString();
    return os;
  }

 private:
  static const int _base = 1000 * 1000 * 1000;
  std::vector<int> _data;
  int _cmp(const BigInteger &a, const BigInteger &b) const {
    if (a._data.size() > b._data.size()) return 1;
    if (a._data.size() < b._data.size()) return -1;
    for (int i = (int)a._data.size() - 1; i >= 0; i--) {
      if (a._data[i] > b._data[i]) return 1;
      if (a._data[i] < b._data[i]) return -1;
    }
    return 0;
  }
  BigInteger _div_short(const BigInteger &c, int b, int &mod) const {
    mod = 0;
    BigInteger a = c;
    for (int i = (int)a._data.size() - 1; i >= 0; i--) {
      long long cur = a._data[i] + mod * 1ll * BigInteger::_base;
      a._data[i] = int(cur / b);
      mod = int(cur % b);
    }
    while (a._data.size() > 1 && a._data.back() == 0) a._data.pop_back();
    return a;
  }
  bool _is_zero() const { return _data.size() == 1 && _data[0] == 0; }
};
const BigInteger operator+(const BigInteger &i) { return BigInteger(i); }
const BigInteger &operator++(BigInteger &i) {
  int j = 0;
  i._data[0]++;
  while (i._data[j] >= BigInteger::_base) {
    if (j == (int)i._data.size() - 1)
      i._data.push_back(1);
    else
      i._data[j + 1]++;
    i._data[j] -= BigInteger::_base;
    j++;
  }
  return i;
}
const BigInteger operator++(BigInteger &i, int) {
  BigInteger old = BigInteger(i);
  int j = 0;
  i._data[0]++;
  while (i._data[j] >= BigInteger::_base) {
    if (j == (int)i._data.size() - 1)
      i._data.push_back(1);
    else
      i._data[j + 1]++;
    i._data[j] -= BigInteger::_base;
    j++;
  }
  return old;
}
const BigInteger &operator--(BigInteger &i) {
  if (!i._is_zero()) i = i - 1;
  return i;
}
const BigInteger operator--(BigInteger &i, int) {
  BigInteger old = BigInteger(i);
  if (!i._is_zero()) i = i - 1;
  return old;
}
const BigInteger operator+(const BigInteger &c, const BigInteger &b) {
  BigInteger a = c;
  int carry = 0;
  for (size_t i = 0; i < std::max(a._data.size(), b._data.size()) || carry;
       i++) {
    if (i == a._data.size()) a._data.push_back(0);
    a._data[i] += carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] >= BigInteger::_base;
    if (carry) a._data[i] -= BigInteger::_base;
  }
  return a;
}
const BigInteger operator-(const BigInteger &c, const BigInteger &b) {
  if (c < b)
    throw std::invalid_argument("a - b, a must b greater or equal zero");
  BigInteger a = c;
  int carry = 0;
  for (size_t i = 0; i < b._data.size() || carry; i++) {
    a._data[i] -= carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] < 0;
    if (carry) a._data[i] += BigInteger::_base;
  }
  while (a._data.size() > 1 && a._data.back() == 0) a._data.pop_back();
  return a;
}
const BigInteger operator*(const BigInteger &a, const BigInteger &b) {
  BigInteger c;
  c._data.resize(a._data.size() + b._data.size());
  for (size_t i = 0; i < a._data.size(); i++)
    for (int j = 0, carry = 0; j < (int)b._data.size() || carry; j++) {
      long long cur =
          c._data[i + j] +
          a._data[i] * 1ll * (j < (int)b._data.size() ? b._data[j] : 0) + carry;
      c._data[i + j] = int(cur % BigInteger::_base);
      carry = int(cur / BigInteger::_base);
    }
  while (c._data.size() > 1 && c._data.back() == 0) c._data.pop_back();
  return c;
}
const BigInteger operator/(const BigInteger &a, const BigInteger &b) {
  if (b._is_zero()) throw std::invalid_argument("division by zero");
  BigInteger l = 0, r = a + 1, m;
  int t;
  while (r - l > 1) {
    m = a._div_short(r + l, 2, t);
    if (b * m <= a)
      l = m;
    else
      r = m;
  }
  return l;
}
const BigInteger operator%(const BigInteger &a, const BigInteger &b) {
  if (b._is_zero()) throw std::invalid_argument("division by zero");
  BigInteger l = 0, r = a + 1, m;
  int t;
  while (r - l > 1) {
    m = a._div_short(r + l, 2, t);
    if (b * m <= a)
      l = m;
    else
      r = m;
  }
  return a - b * l;
}
BigInteger &operator+=(BigInteger &a, const BigInteger &b) {
  int carry = 0;
  for (size_t i = 0; i < std::max(a._data.size(), b._data.size()) || carry;
       i++) {
    if (i == a._data.size()) a._data.push_back(0);
    a._data[i] += carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] >= BigInteger::_base;
    if (carry) a._data[i] -= BigInteger::_base;
  }
  return a;
}
BigInteger &operator-=(BigInteger &a, const BigInteger &b) {
  int carry = 0;
  for (size_t i = 0; i < b._data.size() || carry; i++) {
    a._data[i] -= carry + (i < b._data.size() ? b._data[i] : 0);
    carry = a._data[i] < 0;
    if (carry) a._data[i] += BigInteger::_base;
  }
  while (a._data.size() > 1 && a._data.back() == 0) a._data.pop_back();
  return a;
}
BigInteger &operator*=(BigInteger &a, const BigInteger &b) {
  a = a * b;
  return a;
}
BigInteger &operator/=(BigInteger &a, const BigInteger &b) {
  a = a / b;
  return a;
}
BigInteger &operator%=(BigInteger &a, const BigInteger &b) {
  a = a % b;
  return a;
}
bool operator==(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) == 0;
}
bool operator<=(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) <= 0;
}
bool operator>=(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) >= 0;
}
bool operator<(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) < 0;
}
bool operator>(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) > 0;
}
bool operator!=(const BigInteger &a, const BigInteger &b) {
  return a._cmp(a, b) != 0;
}
BigInteger binpow(BigInteger a, BigInteger n) {
  if (n == 0) return 1;
  if (n % 2 == 1)
    return binpow(a, n - 1) * a;
  else {
    BigInteger b = binpow(a, n / 2);
    return b * b;
  }
}
BigInteger gcd(BigInteger a, BigInteger b) {
  if (b == 0)
    return a;
  else
    return gcd(b, a % b);
}
long long int gcd(long long int a, long long int b) {
  return b ? gcd(b, a % b) : a;
}
int gcd(int a, int b) { return b ? gcd(b, a % b) : a; }
struct element {
  int x;
  element *Next;
};
class List {
  element *Head;

 public:
  List() { Head = NULL; }
  ~List();
  void Add(int x);
  void Show();
  void Delete();
  void Sort();
};
List::~List() {
  while (Head != NULL) {
    element *temp = Head->Next;
    delete Head;
    Head = temp;
  }
}
void List::Add(int x) {
  element *temp = new element;
  temp->x = x;
  temp->Next = Head;
  Head = temp;
}
void List::Show() {
  element *temp = Head;
  while (temp != NULL) {
    cout << temp->x << " ";
    temp = temp->Next;
  }
}
void List::Delete() {
  int k;
  cin >> k;
  element *temp = Head;
  element *prev = 0;
  while (temp) {
    element *next = temp->Next;
    if (temp->x == k) {
      if (prev) prev->Next = next;
      delete temp;
    } else {
      prev = temp;
    }
    temp = next;
  }
}
void List::Sort() {
  element *temp = Head;
  while (temp->Next) {
    if (temp->x > temp->Next->x) {
      swap(temp->x, temp->Next->x);
      temp = temp->Next;
      Sort();
    } else
      temp = temp->Next;
  }
}
int main() {
  int n;
  cin >> n;
  vector<char> a, b;
  char x;
  cin >> x;
  a.push_back(x);
  for (int i = 1; i < n; i++) {
    cin >> x;
    if (a.size() % 2 == 0)
      a.push_back(x);
    else if (x != a[a.size() - 1])
      a.push_back(x);
    if (b.size() == 0 || b.size() % 2 == 0)
      b.push_back(x);
    else if (x != b[b.size() - 1])
      b.push_back(x);
  }
  int maxi = max(a.size(), b.size());
  if (maxi % 2 == 1) maxi--;
  cout << n - maxi << endl;
  if (a.size() > b.size()) {
    int n = a.size();
    if (a.size() % 2 == 1) n--;
    for (int i = 0; i < n; i++) cout << a[i];
  } else {
    int n = b.size();
    if (b.size() % 2 == 1) n--;
    for (int i = 0; i < n; i++) cout << b[i];
  }
}

```