#include <bits/stdc++.h>
using namespace std;
int n, in, out;
string s, a, b;
map<string, vector<char>> adjList;
map<string, bool> visited;
map<string, int> indegree, outdegree;
set<string> sets;
vector<char> cur, circuit;
void hierholzer(string t, char c) {
  if (c != '#') {
    cur.push_back(c);
  }
  while (!adjList[t].empty()) {
    char ch = adjList[t].back();
    adjList[t].pop_back();
    s = "";
    s += t[1];
    s += ch;
    hierholzer(s, ch);
  }
  if (!cur.empty()) {
    circuit.push_back(cur.back());
    cur.pop_back();
  }
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(0);
  cout.tie(0);
  cin >> n;
  for (int i = 0; i < n; i++) {
    cin >> s;
    a = "";
    a += s[0];
    a += s[1];
    b = "";
    b += s[1];
    b += s[2];
    adjList[a].push_back(s[2]);
    outdegree[a]++;
    indegree[b]++;
    sets.insert(a);
    sets.insert(b);
  }
  for (auto it = sets.begin(); it != sets.end(); it++) {
    a = *it;
    if (indegree[a] == outdegree[a] + 1) {
      in++;
    } else if (indegree[a] + 1 == outdegree[a]) {
      out++;
      circuit.push_back(a[0]);
      circuit.push_back(a[1]);
    } else if (indegree[a] != outdegree[a]) {
      cout << "NO\n";
      return 0;
    }
  }
  if ((in == 1 && out == 1) || (in == 0 && out == 0)) {
    if (in == 0 && out == 0) {
      circuit.push_back(a[0]);
      circuit.push_back(a[1]);
    }
    s = "";
    s += circuit[0];
    s += circuit[1];
    hierholzer(s, '#');
    if (circuit.size() == n + 2) {
      cout << "YES\n";
      cout << circuit[0] << circuit[1];
      for (int i = circuit.size() - 1; i >= 2; i--) {
        cout << circuit[i];
      }
    } else {
      cout << "NO\n";
    }
  } else {
    cout << "NO\n";
  }
  return 0;
}
