#include <bits/stdc++.h>
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
using namespace std;
const long double PI = acos(-1);
const int N = 2e6 + 10;
const int mod = 1e9 + 7;
const int mod1 = 998244353;
const long long INF = 2e18;
long long xyp(long long x, long long y, long long mod) {
  if (y == 0) return 1LL;
  if (y == 1) return x;
  if (y % 2) {
    long long p = xyp(x, y - 1, mod);
    return (x * p) % mod;
  }
  long long p = xyp(x, y / 2, mod);
  return (p * p) % mod;
}
long long add(long long a, long long b) {
  return (a % mod + b % mod + mod) % mod;
}
long long sub(long long a, long long b) {
  return (a % mod - b % mod + mod) % mod;
}
long long mul(long long a, long long b) {
  return ((a % mod) * (b % mod) + mod) % mod;
}
long long xx[4] = {1, 0, -1, 0};
long long yy[4] = {0, 1, 0, -1};
template <class T>
ostream& operator<<(ostream& os, vector<T> V) {
  os << "[ ";
  for (auto v : V) os << v << " ";
  return os << "]";
}
template <class T>
ostream& operator<<(ostream& os, set<T> second) {
  os << "{ ";
  for (auto s : second) os << s << " ";
  return os << "}";
}
template <class L, class R>
ostream& operator<<(ostream& os, pair<L, R> P) {
  return os << "(" << P.first << "," << P.second << ")";
}
template <class L, class R>
ostream& operator<<(ostream& os, map<L, R> M) {
  os << "{ ";
  for (auto m : M) os << "(" << m.first << ":" << m.second << ")";
  return os << "}";
}
template <typename Arg1>
void __f(const char* name, Arg1&& arg1) {
  cout << name << " : " << arg1 << std::endl;
}
template <typename Arg1, typename... Args>
void __f(const char* names, Arg1&& arg1, Args&&... args) {
  const char* comma = strchr(names + 1, ',');
  cout.write(names, comma - names) << " : " << arg1 << " | ";
  __f(comma + 1, args...);
}
long long in[400005];
vector<int> v[500004];
string ans;
void dfs(long long n) {
  for (; v[n].size();) {
    long long where = v[n].back();
    v[n].pop_back();
    dfs(where);
  }
  ans += (n) % 130;
}
void solve() {
  long long n;
  cin >> n;
  for (long long i = 0; i < n; i++) {
    string s;
    cin >> s;
    long long ind1 = s[0] * 130 + s[1];
    long long ind2 = s[1] * 130 + s[2];
    v[ind1].push_back(ind2);
    in[ind2]++;
  }
  for (long long i = 0; i < 300004; i++) {
    if (abs(in[i] - (long long)v[i].size()) > 1LL) {
      cout << "NO" << endl;
      return;
    }
  }
  long long ind = -1;
  for (long long i = 0; i < 300005; i++) {
    if (v[i].size() - in[i] == 1) {
      if (ind != -1) {
        cout << "NO" << endl;
        return;
      }
      ind = i;
    }
  }
  if (ind == -1)
    for (long long i = 0; i < 300005; i++) {
      if (v[i].size()) ind = i;
    }
  dfs(ind);
  ans += ind / 130;
  reverse(ans.begin(), ans.end());
  if (ans.length() == n + 2) {
    cout << "YES" << endl;
    cout << ans << endl;
  } else {
    cout << "NO" << endl;
  }
}
int main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  cout << fixed << setprecision(6);
  { solve(); }
  return 0;
}
