import sys from collections import defaultdict, Counter, deque from itertools import permutations, combinations, product, combinations_with_replacement, groupby, accumulate import operator from math import sqrt, gcd, factorial # from math import isqrt, prod,comb # python3.8用(notpypy) #from bisect import bisect_left,bisect_right #from functools import lru_cache,reduce #from heapq import heappush,heappop,heapify,heappushpop,heapreplace #import numpy as np #import networkx as nx #from networkx.utils import UnionFind #from numba import njit, b1, i1, i4, i8, f8 #from scipy.sparse import csr_matrix #from scipy.sparse.csgraph import shortest_path, floyd_warshall, dijkstra, bellman_ford, johnson, NegativeCycleError # numba例 @njit(i1(i4[:], i8[:, :]),cache=True) 引数i4配列、i8 2次元配列,戻り値i1 def input(): return sys.stdin.readline().rstrip() def divceil(n, k): return 1+(n-1)//k # n/kの切り上げを返す def yn(hantei, yes='Yes', no='No'): print(yes if hantei else no) def main(): mod = 10**9+7 mod2 = 998244353 n, m, k = map(int, input().split()) graph = [[] for _ in range(n)] for i in range(m): a, b, c = map(lambda x: int(x)-1, input().split()) graph[a].append((b, c+1)) graph[b].append((a, c+1)) dist = [-1]*n kans = 1 lessk = 1 for i in range(n): if dist[i] != -1: continue dist[i] = [1, 0] d = deque() d.append(i) used = dict() point = set([i]) while d: v = d.popleft() for i, num in graph[v]: used[(v, i)] = num if dist[i] != -1: continue dist[i] = [-dist[v][0], -dist[v][1]+num] point.add(i) d.append(i) kakutei = None for (a, b), num in used.items(): aa1, aa2 = dist[a] bb1, bb2 = dist[b] if aa1+bb1 == 0: if aa2+bb2 != num: print(0) return else: if (aa2+bb2) % 2 == 1: print(0) return else: if kakutei == None: kakutei = (num-aa2-bb2)//(aa1+bb1) elif kakutei != (num-aa2-bb2)//(aa1+bb1): print(0) return if kakutei == None: plusmax = max(dist[p][1] if dist[p][0] == 1 else -10**10 for p in point) plusmin = min(dist[p][1] if dist[p][0] == 1 else 10**10 for p in point) minusmax = max(dist[p][1] if dist[p][0] == - 1 else -10**10 for p in point) minusmin = min(dist[p][1] if dist[p][0] == - 1 else 10**10 for p in point) kans *= max(0, min(k-plusmax, minusmin-1) - max(-plusmin+1, -k+minusmax)+1) kans %= mod lessk *= max(0, min(k-1-plusmax, minusmin-1) - max(-plusmin+1, -k+1+minusmax)+1) lessk %= mod else: kans *= int(all(1 <= dist[p][0]*kakutei + dist[p][1] <= k for p in point)) lessk *= int(all(1 <= dist[p][0]*kakutei + dist[p][1] <= k-1 for p in point)) print((kans-lessk)%mod) #print(kans,lessk,kakutei,dist,min(k-plusmax, minusmin+1),max(-plusmin-1, -k+minusmax)) if __name__ == '__main__': main()