import sys

# sys.setrecursionlimit(1000005)
# sys.set_int_max_str_digits(200005)
int1 = lambda x: int(x)-1
pDB = lambda *x: print(*x, end="\n", file=sys.stderr)
p2D = lambda x: print(*x, sep="\n", end="\n\n", file=sys.stderr)
def II(): return int(sys.stdin.readline())
def LI(): return list(map(int, sys.stdin.readline().split()))
def LLI(rows_number): return [LI() for _ in range(rows_number)]
def LI1(): return list(map(int1, sys.stdin.readline().split()))
def LLI1(rows_number): return [LI1() for _ in range(rows_number)]
def SI(): return sys.stdin.readline().rstrip()

# dij = [(0, 1), (-1, 0), (0, -1), (1, 0)]
dij = [(0, 1), (-1, 0), (0, -1), (1, 0), (1, 1), (1, -1), (-1, 1), (-1, -1)]
# inf = -1-(-1 << 31)
inf = -1-(-1 << 62)

md = 10**9+7
# md = 998244353

from collections import defaultdict

n,m,k=LI()
to=[[] for _ in range(n)]
uv2z=defaultdict(int)
for _ in range(m):
    u,v,z=LI()
    u,v=u-1,v-1
    to[u].append(v)
    to[v].append(u)
    uv2z[u,v]=uv2z[v,u]=z

def dfs(root=0):
    aa[root]=1
    stack = [(u, root) for u in to[root]]
    lmin=rmin=inf
    lmax=rmax=-inf
    while stack:
        u, p = stack.pop()
        z = uv2z[u, p]
        if aa[u]:
            if aa[u]==aa[p]:
                # 2x=au(z-bu-bp)
                x2=aa[u]*(z-bb[u]-bb[p])
                if x2 < 2 or x2 > k*2 or x2&1:
                    print(0)
                    exit()
                x=x2//2
                if xx[root]==None:
                    xx[root]=x
                elif xx[root]!=x:
                    print(0)
                    exit()
            elif bb[u]!=bb[p]:
                print(0)
                exit()
        else:
            parent[u]=p
            aa[u]=-aa[p]
            bb[u]=z-bb[p]
            if aa[u]==1:
                lmin,lmax=min(lmin,bb[u]),max(lmax,bb[u])
            else:
                rmin, rmax = min(rmin, bb[u]), max(rmax, bb[u])
            for v in to[u]:
                if aa[v]:continue
                stack.append((v,u))
    # x+lmin>=1
    # x>=1-lmin
    # -x+rmin>=1
    # x<=rmin-1
    # x+lmax<=k
    # x<=k-lmax
    # -x+rmax<=k
    # x>=rmax-k
    if xx[root]==None:
        mn=max(1-lmin,rmax-k,1)
        mx=min(rmin-1,k-lmax,k)
        a1=max(0,mx-mn+1)
        mn=max(1-lmin,rmax-k+1,1)
        mx=min(rmin-1,k-1-lmax,k-1)
        a2=max(0,mx-mn+1)
        return a1,a2
    x=xx[root]
    if x+lmin<1 or -x+rmin<1:
        print(0)
        exit()
    a1=a2=0
    if x+lmax<=k and -x+rmax<=k:a1=1
    if x+lmax<k and -x+rmax<k:a2=1
    return a1,a2

parent = [-1]*n
aa=[0]*n
bb=[0]*n
xx=[None]*n

s1=s2=1
for u in range(n):
    if aa[u]:continue
    a1,a2=dfs(u)
    s1*=a1
    s2*=a2
    s1%=md
    s2%=md
    # print(u,a1,a2,s1,s2)

# print(aa)
# print(bb)
# print(xx)
print((s1-s2)%md)