#include <iostream>
#include <math.h>
#include <string>
#include <sstream>
#include <algorithm>
#include <vector>
#include <utility>
#include <stdio.h>
#include <unordered_map>
#include <cstring>
#include <numeric>
#include <set>
#include <map>
#include <queue>
#define Kaspárov main
using namespace std;
#pragma GCC optimize("Ofast,unroll-loops")
//\\ PRINCIPAL \\//
//#define int long long
#define ull unsigned long long
#define ios ios_base::sync_with_stdio(0); cin.tie(nullptr); cout.tie(nullptr); cout.setf(ios::fixed); cout.precision(0); //srand(time(NULL));
//\\ VECTOR \\//
#define vi vector<int>
#define pii pair<int, int>
#define ti pair<int, pii>
#define vii vector<vector<int>>
#define vpii vector<pair<int, int>>
#define vti vector<ti>
#define vipii vector<vector<pair<int, int>>>
#define pb push_back
#define ff first
#define ss second
#define pb push_back
#define all(x) (x).begin(), (x).end()
#define lb lower_bound
#define ordenar(x) sort( x.begin(), x.end() )
#define ordenarA(x,n) sort( x, x + n )
#define dbg(x) cout<<#x<<": "<<x<<"\n"
#define forn(i, n) for(int i = 0; i<n; ++i)
#define For(i, a, n) for(int i = a; i<n; ++i)
//\\ OPERACIONES RAPIDAS \\//
#define sf(n) scanf("%d", &n)
#define sff(n,m) scanf("%d%d",&n,&m)
#define sfl(n) scanf("%lld", &n)
#define sffl(n,m) scanf("%lld%lld",&n,&m)
#define pf(n) printf("%d\n",n)
#define pfl(n) printf("%lld ",n)
#define pfs(s) printf("%s\n",s)
bool cmp1(pii a, pii b){
return a.ss<b.ss;
}
bool cmp2(ti a, ti b){
return a.ss.ff<b.ss.ff;
}
bool cmp3(ti a, ti b){
return a.ss.ss<b.ss.ss;
}
//\\ CODEFORCES \\//
#define ri(v, size) vector<int> v(size); for(int& x: v) cin>>x;
#define rpi(v, size) vector<pair<int, int>> v(size); for(auto& x: v) cin>>x.ff>>x.ss;
#define rt(n, size) vti(size); for(auto& x: v) cin>>x.ff>>x.ss.ff>>x.ss.ss;
#define srt(v) sort(all(v))
#define srt1(v) sort(all(v), cmp1)
#define srt2(v) sort(all(v), cmp2)
#define srt3(v) sort(all(v), cmp3)
#define yesr {cout<<"YES\n"; return;}
#define nor {cout<<"NO\n"; return;}
#define yes cout<<"YES\n"
#define no cout<<"NO\n"
inline void es(bool a){
string res = a==true ? "YES\n" : "NO\n";
cout<<res;
}
const int MAXN = 5e5+5, mod = 1e9+7;
const int INF = 1e18;
inline void mos(vector<int> a){
for(int x: a) cout<<x<<" ";
cout<<"\n";
}
void setIO(string name = "") {
if (!name.empty()) {
freopen((name + ".in").c_str(), "r", stdin);
freopen((name + ".out").c_str(), "w", stdout);
}
}
vi p(MAXN);
void sieve(){
forn(i, MAXN) p[i] = i;
for(int i = 2; i*i<MAXN; ++i){
if(p[i] == i){
for(int j = i*i; j<MAXN; j+=i) p[j] = i;
}
}
}
void solve();
int nextt = 0;
vii trie(MAXN, vi(26, 0));
vi fin(MAXN, 0), xlr8(MAXN, 0);
void insert(string w, int y){
int nodo = 0;
for(char c: w){
if(trie[nodo][c-'a'] == 0){
trie[nodo][c-'a'] = ++nextt;
}
nodo = trie[nodo][c-'a'];
xlr8[nodo] = max(xlr8[nodo], y);
}
fin[nodo] = 1;
}
string res = "";
void dfs(int nodo = 0){
if(fin[nodo]) res+= 'P';
int zzz = -1;
forn(i, 26){
if(trie[nodo][i]==0) continue;
if(xlr8[trie[nodo][i]]){ zzz = i; continue;}
char c = ('a'+i);
//cout<<c<<endl;
res += c;
dfs(trie[nodo][i]);
}
if(zzz != -1){
char c = ('a' + zzz);
res += c;
dfs(trie[nodo][zzz]);
}
if(!xlr8[nodo]) res += '-';
}
int32_t main(){
setIO();
ios;
sieve();
int t = 1;
while(t--){
solve();
}
fflush(stdin);
fflush(stdout);
}
void solve(){
int n; cin>>n;
int maxn = 0, idx;
vector<string> vs(n);
forn(i, n){
cin>>vs[i];
if(vs[i].size()>maxn){ maxn = vs[i].size(); idx = i;}
}
forn(i, n){
insert(vs[i], (i==idx));
}
dfs();
cout<<res.size()-1<<"\n";
forn(i, res.size()-1) cout<<res[i]<<"\n";
}
/*
3
print
the
poem
*/
