#include <bits/stdc++.h>
using namespace std;
#define LOCAL
#define L(i, j, n) for (int i = (j); i < (int)n; i ++)
#define LI(i, j, n) for (int i = (j); i <= (int)n; i ++)
#define R(i, j, n) for (int i = (j); i > (int)n; i --)
#define RI(i, j, n) for (int i = (j); i >= (int)n; i --)
#define SZ(x) int((x).size())
#define ALL(x) begin(x),end(x)
#define IS_IN(x, v) ((x).find(v) != (x).end())
#define vec vector
#define pb push_back
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
const int N = (int)2e5+5;
const int MOD = (int)1e9 + 7;
const int oo = (int)1e9;
vec<char> sol;
struct trie{
trie* ch[26];
int height;
// int dp[26];
bool eee;
trie(){
eee=0;
height=0;
L(i,0,26){
ch[i]=0;
// dp[i]=-oo;
}
}
void insert(string &s, int i){
if (SZ(s) == i){
eee = 1;
// dp[i] = max(1, dp[i]);
height = max(height, 1);
// cout << "H: " << height << "\n";
return;
}
int id = s[i] - 'a';
if (ch[id]==0) ch[id] = new trie;
ch[id]->insert(s, i + 1);
height = max(height, ch[id]->height + 1);
// dp[id] = max(height + 1, height);
}
void insert(string &s){
trie*cur=this;
for(char c:s){
int id=c-'a';
if(cur->ch[id]==0)cur->ch[id]=new trie;
cur=cur->ch[id];
}
cur->eee = 1;
}
void print(){
if (eee){
sol.pb('P');
}
vec<pii> ord;
L(i,0,26){
if (ch[i] != 0){
ord.pb({ch[i]->height, i});
}
}
if (SZ(ord))
sort(ALL(ord));
for (auto &[f,s]:ord) {
sol.pb(char('a'+s));
// cout << s << " -> " << f << "\n";
ch[s]->print();
sol.pb('-');
}
}
} *root;
void solve()
{
int n; cin >> n;
root = new trie;
L(i,0,n){
string s; cin >> s;
root->insert(s, 0);
}
// cout << "PrePrint" << endl;
root->print();
// cout << "PosPrint" << endl;
while(!sol.empty() && sol.back()=='-') sol.pop_back();
cout << SZ(sol) << endl;
for(char c: sol){
cout << c << '\n';
}
}
int main()
{
ios::sync_with_stdio(0);cin.tie(0);
int TT = 1;
//cin >> TT;
while (TT--)
{
solve();
}
}
