#include <bits/stdc++.h>
using namespace std;
#define REP(i,a,n) for(int i=(a); i<(int)(n); i++)
#define rep(i,n) REP(i,0,n)
#define FOR(it,c) for(__typeof((c).begin()) it=(c).begin(); it!=(c).end(); ++it)
#define ALLOF(c) (c).begin(), (c).end()
typedef long long ll;
typedef unsigned long long ull;

#define MOD 1000000007

int H, W, K, P;
int x[20];
int y[20];
string name[20];


int main(){
  cin >> H >> W >> K >> P;
  rep(i,K){
    cin >> x[i] >> y[i] >> name[i];
  }

  double mx = 0;
  ll mx_mod = 0;
  ll mx_S = 0;
  for(ll S=0; S<(1<<K); S++){
    int cnt = 0;
    vector<vector<int>> f(H+1, vector<int>(W+1, 0));
    vector<vector<ll>> dp(H+1, vector<ll>(W+1, 0));
    vector<vector<double>> dp2(H+1, vector<double>(W+1, 0));
    rep(i,K){
      if((S>>i)&1){
        cnt++;
      }else{
        f[x[i]][y[i]] = -1;
      }
    }
    if(cnt>P) continue;
    dp[0][0] = 1;
    dp2[0][0] = 1;
    rep(i,H+1){
      rep(j,W+1){
        if(i==0 && j==0) continue;
        if(f[i][j] == -1) continue;
        if(i-1>=0){
          dp[i][j] += dp[i-1][j];
          dp2[i][j] += dp2[i-1][j];
        }
        dp[i][j] %= MOD;
        if(j-1>=0){
          dp[i][j] += dp[i][j-1];
          dp2[i][j] += dp2[i][j-1];
        }
        dp[i][j] %= MOD;
      }
    }
    if(mx < dp2[H][W]){
      mx = dp2[H][W];
      mx_mod = dp[H][W];
      mx_S = S;
    }
  }

  cout << mx_mod << endl;
  rep(i,K){
    if((mx_S>>i)&1){
      cout << name[i] << endl;
    }
  }
  
  return 0;
}