#include <bits/stdc++.h>
using namespace std;
long long Set(long long N, long long pos) { return N = N | (1 << pos); }
long long reset(long long N, long long pos) { return N = N & ~(1 << pos); }
bool check(long long N, long long pos) { return (bool)(N & (1 << pos)); }
void CI(int &_x) { scanf("%d", &_x); }
void CO(long long &_x) { cout << _x; }
template <typename T>
void getarray(T a[], long long n) {
  for (long long i = 0; i < n; i++) cin >> a[i];
}
template <typename T>
void prLLIarray(T a[], long long n) {
  for (long long i = 0; i < n - 1; i++) cout << a[i] << " ";
  cout << a[n - 1] << endl;
}
const double EPS = 1e-9;
const long long INF = 0x7f7f7f7f;
long long dr8[8] = {1, -1, 0, 0, 1, -1, -1, 1};
long long dc8[8] = {0, 0, -1, 1, 1, 1, -1, -1};
long long dr4[4] = {0, 0, 1, -1};
long long dc4[4] = {-1, 1, 0, 0};
long long kn8r[8] = {1, 2, 2, 1, -1, -2, -2, -1};
long long kn8c[8] = {2, 1, -1, -2, -2, -1, 1, 2};
map<string, vector<string> > G;
map<string, int> indegree, outdegree, kount;
set<string> S;
bool check_euler(int k1, int k2, int k3) {
  if ((k2 == 0 && k3 == 0 && k1 == S.size()) ||
      (k2 == 1 && k3 == 1 && k1 == S.size() - 2)) {
    return 1;
  }
  return 0;
}
map<pair<string, string>, bool> deleted;
vector<string> path;
int edges = 0;
void dfs(string u) {
  for (; kount[u] < G[u].size();) {
    string v = G[u][kount[u]];
    kount[u]++;
    dfs(v);
  }
  edges++;
  path.push_back(u);
}
int main() {
  int n;
  cin >> n;
  for (long long i = 0; i < n; i++) {
    string str;
    cin >> str;
    string u = "", v = "";
    u = u + str[0] + str[1];
    v = v + str[1] + str[2];
    G[u].push_back(v);
    S.insert(u), S.insert(v);
    indegree[v]++;
    outdegree[u]++;
  }
  __typeof(S.begin()) it;
  string start = "";
  int k1 = 0, k2 = 0, k3 = 0;
  for (it = S.begin(); it != S.end(); it++) {
    if (start == "") start = *it;
    if (indegree[*it] == outdegree[*it]) {
      k1++;
    } else if (outdegree[*it] - indegree[*it] == 1) {
      k2++;
      start = *it;
    } else if (indegree[*it] - outdegree[*it] == 1) {
      k3++;
    }
  }
  if (check_euler(k1, k2, k3) == 0) {
    puts("NO");
    return 0;
  }
  dfs(start);
  if (edges != n + 1) {
    puts("NO");
  } else {
    puts("YES");
    reverse(path.begin(), path.end());
    cout << path[0];
    for (int i = 1; i < path.size(); i++) cout << path[i][1];
    puts("");
  }
}
