#include <fstream>
#include <cstring>

using namespace std;
char a[20005][25];
int save[20005],savemax[20005];


int main(){
    int i,j,n,st = 0,cont = 1, maxi = 1;
    char elcur;
    ifstream fin("text3.in");
    ofstream fout("text3.out");

    while(fin >> a[++st]){}

    fout<<st - 1;
    fout<<"\n";

    for(i = 1; i < st; ++i){
        cont = 1;
        save[cont] = i;
        elcur = a[i][strlen(a[i]) - 1];
        for(j = i + 1; j < st; ++j){
            if(a[j][0] == elcur){
                elcur = a[j][strlen(a[j]) - 1];

                cont++;
                save[cont] = j;

            }
        }
        if(cont > maxi){
            for(j = 1; j <= cont; ++j)
                savemax[j] = save[j];
            maxi = cont;
        }


    }
    fout<<(st-1) - maxi;
    fout<<"\n";

    for(i = 1; i <= maxi; ++i){
        for(j = 0; j < strlen(a[savemax[i]]); ++j)
            fout<<a[savemax[i]][j];
        fout<<"\n";
    }
}