#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=a;i<b;i++)


typedef long long ll;
int mod = 1000000007;
int H, W, K, P;
int X[40], Y[40]; string N[40];
//-----------------------------------------------------------------------------------
int B[40][40];
ll cnt[40][40];
ll count() {
    rep(i, 0, 40) rep(j, 0, 40) cnt[i][j] = 0;

    cnt[0][0] = 1;
    rep(y, 0, H + 1) rep(x, 0, W + 1) if(!B[y][x]){
        if (0 < x) cnt[y][x] += cnt[y][x - 1];
        if (0 < y) cnt[y][x] += cnt[y - 1][x];
    }

    return cnt[H][W];
}
//-----------------------------------------------------------------------------------
int main() {
    cin >> H >> W >> K >> P;
    rep(i, 0, K) cin >> X[i] >> Y[i] >> N[i];

    ll ma = 0, ma_f = 0;
    rep(flag, 0, 1 << K) {
        vector<int> friends;
        rep(i, 0, K) if (flag & (1 << i)) friends.push_back(i);
        if (friends.size() != P) continue;

        rep(y, 0, H + 1) rep(x, 0, W + 1) B[y][x] = 0;
        rep(i, 0, K) B[X[i]][Y[i]] = 1;
        for (int i : friends) B[X[i]][Y[i]] = 0;
        ll c = count();
        if (ma < c) {
            ma = c;
            ma_f = flag;
        }
    }

    cout << ma % mod << endl;
    rep(i, 0, K) {
        if (ma_f & (1 << i)) cout << N[i] << endl;
    }
}