#include <bits/stdc++.h>
using namespace std;
bool debug = 1;
int n, m, k;
int dx[4] = {0, 1, 0, -1}, dy[4] = {1, 0, -1, 0};
long long ln, lk, lm;
string rid[200005];
unordered_map<string, int> id;
int cnt, in[200005], out[200005];
vector<int> mp[200005];
void e(int w) {
  puts("NO");
  exit(0);
}
int st = -1, ed = -1;
vector<int> path;
void dfs(int x) {
  while (!mp[x].empty()) {
    int bk = mp[x].back();
    mp[x].pop_back();
    dfs(bk);
  }
  path.push_back(x);
}
void cal() {
  for (int(i) = 1; (i) <= (int)(cnt); (i)++)
    if (in[i] != out[i]) {
      if (in[i] + 1 == out[i]) {
        if (st == -1)
          st = i;
        else
          e(1);
      } else if (in[i] == out[i] + 1) {
        if (ed == -1)
          ed = i;
        else
          e(2);
      } else
        e(3);
    }
  if (st == -1 && ed == -1) st = ed = 1;
  if (st == -1 || ed == -1) e(4);
  dfs(st);
  if (path.size() != n + 1) e(5);
  reverse(path.begin(), path.end());
  string x = rid[path[0]];
  for (int i = 1; i < path.size(); i++) {
    x += rid[path[i]][1];
  }
  cout << ("YES") << endl;
  cout << x << endl;
}
int main() {
  ios::sync_with_stdio(false);
  cin.tie(0);
  cin >> n;
  for (int(i) = 0; (i) < (int)(n); (i)++) {
    string s;
    cin >> s;
    string a = s.substr(0, 2), b = s.substr(1, 2);
    if (id.find(a) == id.end()) {
      id[a] = ++cnt;
      rid[cnt] = a;
    }
    if (id.find(b) == id.end()) {
      id[b] = ++cnt;
      rid[cnt] = b;
    }
    mp[id[a]].push_back(id[b]);
    in[id[b]]++;
    out[id[a]]++;
  }
  cal();
  return 0;
}
