// https://oj.uz/problem/view/IOI08_printer
#include <bits/stdc++.h>
using namespace std;
struct node {
vector<int> child = vector<int> (26, -1);
int h = 0;
bool mark = false;
};
vector<node> t {{}};
void insert (string &s, int id = 0, int i = 0) {
t[i].h = max(t[i].h, (int) s.size() - id);
if (id == s.size()) {
t[i].mark = true;
return;
}
int c = s[id] - 'a';
if (t[i].child[c] == -1) {
t.push_back({});
t[i].child[c] = t.size() - 1;
}
insert(s, id+1, t[i].child[c]);
}
vector<char> sol {};
void comp (int i) {
if (t[i].mark) {
sol.push_back('P');
}
int maxi = -1;
for (int c = 0; c < 26; c++) {
if (t[i].child[c] == -1) continue;
if (t[i].h - 1 == t[t[i].child[c]].h) {
maxi = c;
}
}
for (int c = 0; c < 26; c++) {
if (t[i].child[c] == -1) continue;
if (c == maxi) continue;
sol.push_back(c + 'a');
comp(t[i].child[c]);
sol.push_back('-');
}
if (maxi != -1) {
sol.push_back(maxi + 'a');
comp(t[i].child[maxi]);
sol.push_back('-');
}
}
int main() {
cin.tie(0);
ios::sync_with_stdio(false);
int n;
cin >> n;
for (int i = 0; i < n; i++) {
string s;
cin >> s;
insert(s);
}
comp(0);
while (!sol.empty() && sol[sol.size() - 1] == '-') {
sol.pop_back();
}
cout << sol.size() << "\n";
for (auto &it : sol) {
cout << it << "\n";
}
return 0;
}
