#include<bits/stdc++.h>
using namespace std;
#define int long long
#define F first
#define S second
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define pf push_front
#define pb push_back
#define SZ(x) ((int)(x).size())
#define AhmedPlusPlus ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define YN(X) cout << ( X ? "YES\n" : "NO\n" );
#define hi cerr<<"hi\n";
/* -> NO CLEAN CODE HERE <- */
string ans;
struct Trie {
struct Node {
int children[26] = {};
int f = 0 ,mx = 0, end = 0;
};
vector<Node> trie;
Trie() {
trie.emplace_back();
}
void insert(string& s) {
int idx = 0;
for(auto i : s) {
int nxt = i-'a';
if(trie[idx].children[nxt] == 0) {
trie[idx].children[nxt] = trie.size();
trie.emplace_back();
}
idx = trie[idx].children[nxt];
trie[idx].f++;
}
trie[idx].end++;
}
void pre(int node = 0){
int mxx = 0;
for (int i =0;i<26;i++){
if (trie[node].children[i]) {
pre(trie[node].children[i]);
mxx = max(mxx , trie[trie[node].children[i]].mx);
}
}
trie[node].mx = mxx+1;
}
void solve(int node = 0){
int mxx = 0,men=-1;
for (int i =0;i<26;i++)
if (trie[node].children[i] != 0 && trie[trie[node].children[i]].mx > mxx)
mxx = trie[trie[node].children[i]].mx, men = i;
for (int i =0;i<26;i++){
if (i == men || trie[node].children[i] == 0)continue;
ans+=(char)(i+'a');
solve(trie[node].children[i]);
ans+=(char)('-');
}
if (~men){
ans+=(char)(men+'a');
solve(trie[node].children[men]);
ans+=(char)('-');
}
while (trie[node].end--)
ans+='P';
}
};
void pewpew() {
int n;cin>>n;
string s;
Trie tr;
for (int i =0;i<n;i++){
cin>>s;
tr.insert(s);
}
tr.pre();
tr.solve();
int cnt = 0 , ptr = SZ(ans)-1;
while(ptr && ans[ptr] == '-')
cnt++ , ptr--;
cout << SZ(ans) - cnt << "\n";
for (int i =0;i<SZ(ans)-cnt ; i++ )cout << ans[i] << "\n";
}
signed main() {
/* ^^^ */ AhmedPlusPlus /* ^^^ */
// ->> practice makes perfect
int Hi = 1;
//cin >> Hi;
while (Hi--)
pewpew();
}
