#include <bits/stdc++.h>
using namespace std;
#define int long long
#define pii pair<int, int>
#define all(v) v.begin(), v.end()
const int oo = 1e9 + 9;
const int MAX = 25000 + 5;
int t[30 * MAX][26];
int D[30 * MAX];
int cnt[30 * MAX];
int nxt = 2;
void add(string &s){
int node = 1;
for(int i = 0; i < s.size(); i++){
D[node] = max((int)s.size() - i, D[node]);
if(!t[node][s[i]-'a']) t[node][s[i]-'a'] = nxt++;
node = t[node][s[i]-'a'];
}
cnt[node]++;
}
string ans = "";
void dfs(int node){
if(cnt[node]) ans += 'P';
vector<pii> v;
for(int i = 0; i < 26; i++){
if(!t[node][i]) continue;
v.push_back({D[t[node][i]], i});
}
sort(all(v));
for(auto [d, c] : v){
ans += ('a' + c);
dfs(t[node][c]);
ans += ('-');
}
}
void solve(){
int n; cin >> n;
for(int i = 1; i <= n; i++){
string s; cin >> s;
add(s);
}
dfs(1);
while(ans.back() == '-') ans.pop_back();
cout << ans.size() << '\n';
for(char c : ans) cout << c << '\n';
}
signed main(){
ios::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int t = 1;
// cin >> t;
while(t--) solve();
}
