#include<iostream>
#include<cstdio>
#include<string>
#include<vector>
#include<algorithm>
#define bug puts("----------");
using namespace std;
const int maxn=25005;
int n;
int cnt;
string a,ans;
struct t{
	int nex[30];
	bool visit;
	int num,SIZE;
}tree[maxn];
vector<int> v[maxn];
void qinsert(string s){
	int p=0;
	for(int i=0;i<s.size();i++){
		int c=s[i]-'a';
		if(!tree[p].nex[c])
			tree[p].nex[c]=++cnt;
		p=tree[p].nex[c];	
		tree[p].num=c;
	}
	tree[p].visit=1;
}
void build(int node){
	for(int i=0;i<26;i++)
		if(tree[node].nex[i]){
			v[node].push_back(tree[node].nex[i]);
			build(tree[node].nex[i]);
		}
}
bool cmp(int X,int Y){
	return tree[X].SIZE<tree[Y].SIZE;
}
void dfs(int node){
	tree[node].SIZE++;
	for(int i=0;i<v[node].size();i++){
		dfs(v[node][i]);
//		cout<<node<<' '<<v[node][i]<<' '<<tree[v[node][i]].SIZE<<' '<<tree[node].SIZE<<endl;
//		cout<<tree[node].SIZE<<' '<<tree[v[node][i]].SIZE<<endl;
		tree[node].SIZE+=tree[v[node][i]].SIZE;
//		cout<<tree[node].SIZE<<' '<<tree[v[node][i]].SIZE<<endl;
//		cout<<node<<' '<<v[node][i]<<' '<<tree[v[node][i]].SIZE<<' '<<tree[node].SIZE<<endl;
	}
	sort(v[node].begin(),v[node].end(),cmp);
}
void dfs2(int node,int fa){
	ans+=char(tree[node].num+'a');
	if(tree[node].visit)
		ans+='P';
	for(int i=0;i<v[node].size();i++){
		dfs2(v[node][i],node);
		ans+='-';
	}
}
int main(){
	scanf("%d",&n);
	for(int i=1;i<=n;i++){
		cin>>a;
		qinsert(a);
	}
	build(0);
	dfs(0);
//	for(int i=0;i<=cnt;i++){
//		cout<<i<<endl;
//		for(int j=0;j<v[i].size();j++)
//			cout<<v[i][j]<<' ';
//		cout<<endl;
//	}
	dfs2(0,0);
	int len=ans.size()-1;
	while(ans[len]=='-')
		len--;
	cout<<len<<endl;
	for(int i=1;i<len;i++)
		cout<<char(ans[i])<<endl;
}