text

#include <cstdio>
#include <algorithm>
#include <cstring>
#include <vector>
#define x first
#define y second
#define NMAX 20007
using namespace std;

pair< int, int > Ap[37];
vector< int > SOL;
char a[NMAX][NMAX / 1000];
int Sol[NMAX];

int main()
{
    freopen("text.in", "r", stdin);
    freopen("text.out", "w", stdout);
    int n = 1;
    while(scanf(" %s ", a[n]) == 1){
        int Lung = strlen(a[n]) - 1;
        if(Ap[a[n][Lung] - 'a'].x < Ap[a[n][0] - 'a'].x + 1){
            Ap[a[n][Lung] - 'a'].x = Ap[a[n][0] - 'a'].x + 1;
            Sol[n] = Ap[a[n][0] - 'a'].y;
            Ap[a[n][Lung] - 'a'].y = n;
        }
        ++n;
    }
    printf("%d\n", n - 1);
    int Max = 0, Nr = 0;
    for(int i = 0; i <= 26; ++i)
        if(Max < Ap[i].x){
            Max = Ap[i].x;
            Nr = Ap[i].y;
        }
    printf("%d\n", n - Max - 1);
    while(Nr > 0){
        ///printf("%s\n", a[Nr]);
        SOL.push_back(Nr);
        Nr = Sol[Nr];
    }
    for(int i = SOL.size() - 1; i >= 0; -- i)
        printf("%s\n", a[SOL[i]]);
    return 0;
}