import sys
input=sys.stdin.buffer.readline
sys.setrecursionlimit(10**6)
N,M,K=map(int,input().split())
G=[[] for i in range(N)]
for i in range(M):
  x,y,z=map(int,input().split())
  x-=1
  y-=1
  G[x].append((y,z))
  G[y].append((x,z))
A=[]
ANS=1
ANS2=1
mod=10**9+7
F=[0]*N
X=[]
Y=[[] for i in range(N)]
V=K-1
from collections import *
INF=10**17
for i in range(N):
  if F[i]:
    continue
  for j in range(len(X)-1,-1,-1):
    Y[X[j]].clear()
    del X[j]
  Q=deque([(i,(1,0))])
  while len(Q):
    for _ in range(len(Q)):
      v=Q.popleft()
      X.append(v[0])
      F[v[0]]=1
      Y[v[0]].append(v[1])
      for j in range(len(G[v[0]])-1,-1,-1):
        Q.append((G[v[0]][j][0],(-v[1][0],G[v[0]][j][1]-v[1][1])))
        del G[v[0]][j]
  X=list(set(X))
  L,R=1,K
  L2,R2=1,V
  for j in range(len(X)):
    j=X[j]
    Z=[INF,INF]
    for k in range(len(Y[j])):
      if Y[j][k][0]==1:
        if Z[0]==INF:
          Z[0]=Y[j][k][1]
        else:
          if Z[0]!=Y[j][k][1]:
            L=K+1
            L2=K
      else:
        if Z[1]==INF:
          Z[1]=Y[j][k][1]
        else:
          if Z[1]!=Y[j][k][1]:
            L=K+1
            L2=K
    if Z[0]<INF and Z[1]<INF:
      if (Z[0]^Z[1])&1:
        L=K+1
        L2=K
      else:
        x=(Z[1]-Z[0])>>1
        L=max(L,x)
        L2=max(L2,x)
        R=min(R,x)
        R2=min(R2,x)
    if Z[0]<INF:
      R=min(R,K-Z[0])
      R2=min(R2,V-Z[0])
      L=max(L,-Z[0]+1)
      L2=max(L2,-Z[0]+1)
    if Z[1]<INF:
      R=min(R,Z[1]-1)
      R2=min(R2,Z[1]-1)
      L=max(L,Z[1]-K)
      L2=max(L2,Z[1]-V)
  ANS=ANS*max(0,R-L+1)%mod
  ANS2=ANS2*max(0,R2-L2+1)%mod
print((ANS-ANS2)%mod)