#include <bits/stdc++.h>
using namespace std;
int main() {
cin.tie(0)->sync_with_stdio(0);
int n;
cin >> n;
vector<string> vs(n);
for (auto &a : vs)
cin >> a;
// const int letters = 26;
struct node {
map<char, int> mci;
int ct = 0;
};
vector<node> vn;
vn.emplace_back();
for (auto &a : vs) {
int in = 0;
for (auto c : a) {
if (!vn[in].mci.count(c)) {
vn[in].mci[c] = vn.size();
vn.emplace_back();
}
in = vn[in].mci[c];
}
vn[in].ct++;
}
vector<vector<pair<char, int>>> adj(vn.size());
vector<int> dp(vn.size());
for (int i = 0; i < vn.size(); i++) {
for (auto a : vn[i].mci)
adj[i].push_back(a);
}
function<int(int)> dfs = [&](int cur) {
dp[cur] = 1;
for (auto a : adj[cur])
dp[cur] = max(dp[cur], dfs(a.second) + 1);
return dp[cur];
};
dfs(0);
for (int i = 0; i < vn.size(); i++) {
sort(adj[i].begin(), adj[i].end(),
[&](pair<char, int> a, pair<char, int> b) {
return dp[a.second] < dp[b.second];
});
}
string ans;
int ct = 0;
function<void(int)> dfs2 = [&](int cur) {
if (vn[cur].ct) {
ans.push_back('P');
ct++;
if (ct == n) {
cout << ans.size() << "\n";
for (auto a : ans)
cout << a << "\n";
exit(0);
}
}
for (auto a : adj[cur]) {
ans.push_back(a.first);
dfs2(a.second);
ans.push_back('-');
}
};
dfs2(0);
}
