#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define int long long
#define all(v) v.begin(), v.end()
#define allr(v) v.rbegin(), v.rend()
#define F first
#define S second
#define P push_back
#define endl '\n'
#define pqmn pi , vector<pi> , greater<pi>
const int N = 1e6 + 10;
const int R = 5e3 + 10;
const int mod = 1e9 + 7;
const int inf = 1e9 + 10;
const ll infll = 1e17;
typedef pair<int, int> pi;
typedef vector<int> vi;
typedef vector<pi> vii;
typedef vector<vi> vvi;
typedef vector<vii> vvii;
const int CHAR = 26;
struct trie {
trie* child[CHAR];
int cnt,end , mxlen;
trie() {
memset(child, 0, sizeof child);
cnt = end = 0;
mxlen = 0;
}
void insert(string &str , int i = 0) {
cnt++;
if (i == (int)str.size()) {
end++;
mxlen = max(mxlen , i);
return;
}
int cur = str[i]-'a';
if (child[cur] == 0) child[cur] = new trie();
child[cur]->insert(str , i+1);
mxlen = max(mxlen , child[cur]->mxlen);
}
int dfs(vector<char> &ans){
int count = 0;
for(int i = 0 ; i < end ; i++){
ans.P('P');
count++;
}
struct item{
int mx;
char c;
trie *r;
};
vector<item> arr;
for(char c = 'a' ; c <= 'z' ; c++){
if(child[c - 'a']){
arr.P({child[c - 'a']->mxlen , c , child[c - 'a']});
}
}
sort(all(arr) , [](item a , item b){
if(a.mx < b.mx) return true;
else return false;
});
for(int i = 0 ; i < (int)arr.size() ; i++){
count++;
ans.P(arr[i].c);
count += arr[i].r->dfs(ans);
ans.P('-');
count++;
}
return count;
}
};
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
int n; cin >> n;
trie *root = new trie();
for(int i = 0 ; i < n ; i++){
string s; cin >> s;
root->insert(s);
}
vector<char> ans;
int k = root->dfs(ans);
cout << k - root->mxlen << endl;
for(int i = 0 ; i < k - root->mxlen ; i++){
cout << ans[i] << endl;
}
return 0;
}
