import sys
from itertools import combinations

mod = 10**9 + 7

def solve():
    h, w, k, p = map(int, input().split())
    fr = []

    for i in range(k):
        x, y, name = input().split()
        x = int(x)
        y = int(y)
        fr.append((x, y, name))

    max_keiro = -1
    omit = []

    for cmb in combinations(range(k), k - p):
        dp = [[0]*(h + 1) for i in range(w + 1)]
        taboo = [[False]*(h + 1) for i in range(w + 1)]

        for i in cmb:
            x, y, name = fr[i]
            taboo[y][x] = True

        for x in range(h + 1):
            if taboo[0][x]:
                break
            dp[0][x] = 1

        for y in range(w + 1):
            if taboo[y][0]:
                break
            dp[y][0] = 1

        for y in range(1, w + 1):
            for x in range(1, h + 1):
                if taboo[y][x]:
                    continue

                dp[y][x] = dp[y - 1][x] + dp[y][x - 1]

        if dp[w][h] > max_keiro:
            max_keiro = dp[w][h]
            omit = set(cmb)

    print(max_keiro % mod)

    if max_keiro == 0:
        return

    for i in range(k):
        if i not in omit:
            print(fr[i][2])

if __name__ == '__main__':
    solve()