#include<bits/stdc++.h>
using namespace std;
#define int long long
struct ver {
ver *adj[ 26 ];
int dep = 0;
int mx = 0 ;
int cnt= 0;
ver() {
for ( int i = 0 ; i < 26 ; i++ ) {
adj[ i ] = 0 ;
}
dep = 0 ;
cnt = 0 ;
mx = 0 ;
}
};
string ans;
ver *root = new ver;
void insert( string s ) {
ver *cur = root;
for ( char c : s ) {
if ( !cur -> adj [ c - 'a' ] ) {
cur -> adj[ c - 'a' ] = new ver ;
}
cur = cur -> adj[ c - 'a'];
}
cur -> cnt++;
}
void dfs1 ( ver *cur ) {
cur -> mx = cur -> dep ;
cur -> mx = cur -> dep;
for ( int i = 0 ; i < 26 ; i++ ) {
// cout<<adj[ i ]<<' ';
if ( cur -> adj[ i ] ) {
cur -> adj[ i ] -> dep = cur -> dep + 1 ;
dfs1( cur -> adj[ i ]);
// cur -> mx = max( cur -> mx , cur -> adj [ i ]);
cur -> mx = max(cur -> mx, cur -> adj[ i ] -> mx);
}
}
}
void dfs2 ( ver *cur ) {
// while( cur -> cnt-- ){
// ans+='P';
// }
ans += string(cur -> cnt, 'P');
//for ( int i = 0; i < cur -> cnt ; i++ ) {
// ans +='P';}
int m = -1 ;
for ( int i = 0 ; i < 26 ; i++) {
if ( cur -> adj[ i ] ) {
// cout << adj [ i ] << ' ';
if (m == -1 or cur -> adj[i] -> mx > cur -> adj[ m ] -> mx ) {
m = i;
}
}
}
for (int i = 0 ; i < 26 ; i++) {
if ( i != m and cur -> adj [ i ] ) {
ans += 'a' + i;
dfs2(cur -> adj[ i ]);
ans += '-';
}
}
if (m != -1) {
ans += 'a' + m;
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';
}
}
