text

#include <iostream>
#include <vector>
#include <fstream>
#include <stack>

#define sc -'a'

using namespace std;

ifstream fin("text.in");
ofstream fout("text.out");

short maxim = 0;
short v[20001], a[20001];
vector < string > cuv;



int main()
{
    string s;

    while(fin >> s)
    {
        short aux = -1;

        if(a[s[s.length() - 1] sc] < a[s[0] sc] + 1)
           aux =  a[s[s.length() - 1] sc] = a[s[0] sc] + 1;

        if(aux > maxim)
            maxim = aux;

        cuv.push_back(s);
    }

    fout << cuv.size() << '\n' << cuv.size() - maxim << '\n';

    for(int i = 0; i <= 30; i++)
    {
        fout << a[i] << ' ' << (char)(i + 'a') << '\n';
    }

    for(int i = 0; i <= 30; i++)
    {
        if(a[i] == maxim)
        {
            maxim--;
            fout << cuv[i] << '\n';
            i = -1;
        }
    }


    fin.close();
    fout.close();
    return 0;
}