#include <bits/stdc++.h>
using namespace std;
vector<set<tuple<int, int, int>>> g (2); //l, letter, index
bool fin [200000];
int cnt = 2;
string ans;
void insrt(string s, int i, int idx) {
if (s.size() == i) {
fin[idx] = 1;
return;
}
int next = s[i]-'a';
int idx2 = 0;
int len2 = s.size();
int other = 0;
for (auto [len, let, ind] : g[idx]) {
if (let == next) {
len2 = max(len2, len);
other = len;
idx2 = ind;
break;
}
}
if (idx2 == 0) {
idx2 = cnt;
cnt++;
g.push_back({});
g[idx].insert({len2, next, idx2});
} else {
g[idx].erase({other, next, idx2});
g[idx].insert({len2, next, idx2});
}
insrt(s, i+1, idx2);
}
void dfs(int u) {
if (fin[u]) ans = ans+'P'+'\n';
for (auto [len, let, v] : g[u]) {
ans = ans+char('a'+let)+'\n';
dfs(v);
ans = ans+'-'+'\n';
}
}
signed main() {
ios::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
int n;
cin >> n;
for (int i = 0; i < n; i++) {
string s;
cin >> s;
insrt(s, 0, 1);
}
dfs(1);
while (ans[ans.size()-1] == '-' || ans[ans.size()-1] == '\n') ans.pop_back();
ans = ans + '\n';
cout << ans.size()/2 << '\n' << ans;
}
