#include <bits/stdc++.h>
using namespace std;
#define endl '\n'
typedef long long ll;
const int N = 40;
const int mod = 1e9 + 7;
ll n, m, k, p;
struct Point
{
    ll x, y;
    string name;
} a[N];
bool vis[N][N];
ll f[N][N];
int main(int argc, char const *argv[])
{
    ios::sync_with_stdio(false);
    cin.tie(nullptr), cout.tie(nullptr);
    cin >> n >> m >> k >> p;
    n++, m++;
    for (ll i = 1; i <= k; i++)
    {
        cin >> a[i].x >> a[i].y >> a[i].name;
        a[i].x++, a[i].y++;
    }
    ll ans = -1, ans_S = 0;
    for (ll S = 0; S < (1 << k); S++)
    {
        if (__builtin_popcountll(S) != p)
            continue;
        for (ll i = 1; i <= n; i++)
            for (ll j = 1; j <= m; j++)
                f[i][j] = vis[i][j] = 0;
        for (ll i = 1; i <= k; i++)
            if (!((S >> (i - 1)) & 1))
                vis[a[i].x][a[i].y] = 1;
        f[1][1] = 1;
        for (ll i = 1; i <= n; i++)
            for (ll j = 1; j <= m; j++)
            {
                if (vis[i][j] || (i == 1 && j == 1))
                    continue;
                f[i][j] = f[i - 1][j] + f[i][j - 1];
            }
        if (f[n][m] > ans)
        {
            ans = f[n][m];
            ans_S = S;
        }
    }
    cout << ans % mod << endl;
    if (ans)
        for (ll i = 1; i <= k; i++)
            if ((ans_S >> (i - 1)) & 1)
                cout << a[i].name << endl;
    return 0;
}