// UUID: a0c452bb-5eff-4086-b645-98923e6819e4
#include <bits/stdc++.h>
using namespace std;
vector<vector<int>> trie(250*20+1, vector<int>(26, -1));
vector<bool> iswordend(250*20+1, false);
int nodes = 0;
vector<char> ops;
void insert(const string s){
int node = 0;
for(int i = 0; i < s.size(); i++) {
if (trie[node][s[i] - 'a'] == -1) trie[node][s[i] - 'a'] = ++nodes;
node = trie[node][s[i] - 'a'];
if (i == s.size()-1) iswordend[node]=true;
}
}
void dfs(int node){
if (iswordend[node]) ops.push_back('P');
for(int i = 0; i < 26; i++){
if (trie[node][i] != -1){
ops.push_back((char)i+'a');
dfs(trie[node][i]);
}
}
ops.push_back('-');
}
void solve() {
int n;
cin >> n;
for (int i = 0; i < n; i++){
string s;
cin >> s;
insert(s);
}
dfs(0);
for (int i = ops.size()-1; i >= 0; i--){
if (ops[i] != '-') break;
ops.pop_back();
}
cout << ops.size() << "\n";
for (char c : ops) cout << c << "\n";
return;
}
int main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
int t = 1;
//cin >> t;
while (t--) {
solve();
}
return 0;
}
