h,w,K,P=map(int,input().split())
f=[]
o=[[-1]*(w+1) for i in range(h+1)]
for i in range(K):
  x,y,n=input().split()
  f+=[n]
  x=int(x)
  y=int(y)
  o[x][y]=i
M=10**9+7
v=[[0]*(w+1) for i in range(h+1)]
q=[[[0]*(1<<K) for j in range(w+1)] for i in range(h+1)]
q[0][0][0]=1
v[0][0]=1
for i in range(h+1):
  for j in range(w+1):
    for k in range(1<<K):
      if i+1<=h:
        if o[i+1][j]!=-1:
          if k.bit_count()+1<=K:
            q[i+1][j][k|(1<<o[i+1][j])]+=q[i][j][k]
            v[i+1][j]=1
        else:
          q[i+1][j][k]+=q[i][j][k]
          v[i+1][j]=1
      if j+1<=w:
        if o[i][j+1]!=-1:
          if k.bit_count()+1<=P:
            q[i][j+1][k|(1<<o[i][j+1])]+=q[i][j][k]
            v[i][j+1]=1
        else:
          q[i][j+1][k]+=q[i][j][k]
          v[i][j+1]=1
if v[h][w]:
  for j in range(K):
    for i in range(1<<K):
      if (i>>j)&1:
        q[h][w][i]+=q[h][w][i^(1<<j)]
  a=0
  p=0
  for i in range(1<<K):
    if i.bit_count()<=P:
      if q[h][w][i]>a:
        a=q[h][w][i]
        p=i
  print(a%M)
  for i in range(K):
    if (p>>i)&1:
      print(f[i])
else:
  print(0)