#include "bits/stdc++.h"
#define mod 1000000007
#define inf 4000000000000000000
using namespace std;
#define int long long
struct node{
node* adj[26];
int dep, maxd, num;
node(){
for(int i=0; i<26; i++) adj[i]=0;
dep=0; maxd=0;
num=0;
}
};
string ans;
node* root = new node;
void Insert(string s){
node* cur = root;
for(char c : s) {
if(!cur -> adj[c-'a']) cur -> adj[c-'a'] = new node;
cur = cur->adj[c-'a'];
}
cur -> num++;
}
void dfs1(node* cur){
cur -> maxd = cur -> dep;
for(int i=0; i<26; i++){
if(cur -> adj[i]){
cur -> adj[i] -> dep = cur -> dep +1;
dfs1(cur -> adj[i]);
cur -> maxd=max(cur -> adj[i] -> maxd, cur -> maxd);
}
}
}
void dfs2(node* cur){
while(cur -> num--) ans+="P";
int m=-1;
for(int i=0; i<26; i++){
if(cur -> adj[i]){
if(m==-1 or cur -> adj[i] -> maxd > cur -> adj[m] -> maxd) m=i;
}
}
for(int i=0; i<26; i++) if(cur -> adj[i]){
if(cur -> adj[i] and i!=m){
ans+=i+'a';
dfs2(cur -> adj[i]);
ans+='-';
}
}
if(m!=-1){
ans+=m+'a';
dfs2(cur -> adj[m]);
ans+='-';
}
}
signed main(){
int n; cin>>n;
for(int i=0; i<n; i++){
string s; cin>>s;
Insert(s);
}
dfs1(root); dfs2(root);
while(ans.back()=='-') ans.pop_back();
cout<<ans.size()<<'\n';
for(auto c : ans) cout<<c<<'\n';
}
