#include <bits/stdc++.h>
using namespace std;
using ll = long long;
struct node {
char c;
bool flag;
int d, mxd;
node *ch[26];
node(char c = ' ', bool flag = false, int d = 0, int mxd = 0, bool last = false) : c(c), flag(flag), d(d), mxd(mxd) {
for(int i = 0; i < 26; i++) {
ch[i] = NULL;
}
}
};
void add(node *root, const string &s) {
node *cur = root;
for(auto &c : s) {
if(cur -> ch[c - 'a'] == NULL) {
cur -> ch[c - 'a'] = new node(c);
}
cur = cur -> ch[c - 'a'];
}
cur -> flag = true;
}
void solve() {
int n; cin >> n;
vector<string> s(n);
node *root = new node();
for(auto &str : s) {
cin >> str;
add(root, str);
}
{
auto dfs = [&](auto &&self, node *cur) -> void {
cur -> mxd = cur -> d;
for(int i = 0; i < 26; i++) {
if(cur -> ch[i] != NULL) {
cur -> ch[i] -> d = cur -> d + 1;
self(self, cur -> ch[i]);
cur -> mxd = max(cur -> mxd, cur -> ch[i] -> mxd);
}
}
};
dfs(dfs, root);
}
vector<char> ans;
{
auto dfs = [&](auto &&self, node *cur) -> void {
int j = -1;
for(int i = 0; i < 26; i++) {
if(cur -> ch[i] != NULL && cur -> ch[i] -> mxd == root -> mxd) {
j = i;
break;
}
}
if(cur -> c != ' ') ans.push_back(cur -> c);
if(cur -> flag) ans.push_back('P');
for(int i = 0; i < 26; i++) {
if(cur -> ch[i] != NULL && i != j) {
self(self, cur -> ch[i]);
}
}
if(j != -1) self(self, cur -> ch[j]);
if(cur -> c != ' ') ans.push_back('-');
};
dfs(dfs, root);
}
while(!ans.empty() && ans.back() == '-') ans.pop_back();
cout << ans.size() << '\n';
for(auto &c : ans) cout << c << '\n';
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(nullptr);
solve();
}
