import std.conv, std.functional, std.range, std.stdio, std.string; import std.algorithm, std.array, std.bigint, std.bitmanip, std.complex, std.container, std.math, std.mathspecial, std.numeric, std.regex, std.typecons; import core.bitop; class EOFException : Throwable { this() { super("EOF"); } } string[] tokens; string readToken() { for (; tokens.empty; ) { if (stdin.eof) { throw new EOFException; } tokens = readln.split; } auto token = tokens.front; tokens.popFront; return token; } int readInt() { return readToken.to!int; } long readLong() { return readToken.to!long; } real readReal() { return readToken.to!real; } bool chmin(T)(ref T t, in T f) { if (t > f) { t = f; return true; } else { return false; } } bool chmax(T)(ref T t, in T f) { if (t < f) { t = f; return true; } else { return false; } } int binarySearch(alias pred, T)(in T[] as) { int lo = -1, hi = cast(int)(as.length); for (; lo + 1 < hi; ) { const mid = (lo + hi) >> 1; (unaryFun!pred(as[mid]) ? hi : lo) = mid; } return hi; } int lowerBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a >= val)); } int upperBound(T)(in T[] as, T val) { return as.binarySearch!(a => (a > val)); } struct ModInt(int M_) { import std.conv : to; alias M = M_; int x; this(ModInt a) { x = a.x; } this(long a) { x = cast(int)(a % M); if (x < 0) x += M; } ref ModInt opAssign(long a) { return (this = ModInt(a)); } ref ModInt opOpAssign(string op)(ModInt a) { static if (op == "+") { x += a.x; if (x >= M) x -= M; } else static if (op == "-") { x -= a.x; if (x < 0) x += M; } else static if (op == "*") { x = cast(int)((cast(long)(x) * a.x) % M); } else static if (op == "/") { this *= a.inv(); } else static assert(false); return this; } ref ModInt opOpAssign(string op)(long a) { static if (op == "^^") { if (a < 0) return (this = inv()^^(-a)); ModInt t2 = this, te = ModInt(1); for (long e = a; e > 0; e >>= 1) { if (e & 1) te *= t2; t2 *= t2; } x = cast(int)(te.x); return this; } else return mixin("this " ~ op ~ "= ModInt(a)"); } ModInt inv() const { int a = x, b = M, y = 1, z = 0, t; for (; ; ) { t = a / b; a -= t * b; if (a == 0) { assert(b == 1 || b == -1); return ModInt(b * z); } y -= t * z; t = b / a; b -= t * a; if (b == 0) { assert(a == 1 || a == -1); return ModInt(a * y); } z -= t * y; } } ModInt opUnary(string op: "-")() const { return ModInt(-x); } ModInt opBinary(string op, T)(T a) const { return mixin("ModInt(this) " ~ op ~ "= a"); } ModInt opBinaryRight(string op)(long a) const { return mixin("ModInt(a) " ~ op ~ "= this"); } bool opCast(T: bool)() const { return (x != 0); } string toString() const { return x.to!string; } } enum MO = 10^^9 + 7; alias Mint = ModInt!MO; enum INF = 10L^^18; int N, M; long K; int[] A, B; long[] Z; int[][] G; int[] us; bool[2][] vis; long[2][] val; bool dfs(int u, int s, long c) { if (vis[u][s]) { return (val[u][s] == c); } us ~= u; vis[u][s] = true; val[u][s] = c; foreach (i; G[u]) { const v = A[i] ^ B[i] ^ u; if (!dfs(v, s ^ 1, Z[i] - c)) { return false; } } return true; } void main() { try { for (; ; ) { N = readInt(); M = readInt(); K = readLong(); A = new int[M]; B = new int[M]; Z = new long[M]; foreach (i; 0 .. M) { A[i] = readInt() - 1; B[i] = readInt() - 1; Z[i] = readLong(); } G = new int[][N]; foreach (i; 0 .. M) { G[A[i]] ~= i; G[B[i]] ~= i; } vis = new bool[2][N]; val = new long[2][N]; Mint[2] anss; foreach (s; 0 .. 2) { anss[s] = 1; } foreach (r; 0 .. N) { if (!vis[r][0] && !vis[r][1]) { us = []; if (!dfs(r, 0, 0)) { foreach (t; 0 .. 2) { anss[t] = 0; } goto failed; } us = us.sort.uniq.array; debug { writeln("r = ", r); writeln("us = ", us); writeln("vis = ", vis); writeln("val = ", val); } long[2] lbs, ubs; foreach (t; 0 .. 2) { lbs[t] = -INF; ubs[t] = +INF; } if (vis[r][0] && vis[r][1]) { // x[r] + val[r][0] = -x[r] + val[u][1] if ((val[r][1] - val[r][0]) % 2 != 0) { foreach (t; 0 .. 2) { anss[t] = 0; } goto failed; } const x = (val[r][1] - val[r][0]) / 2; foreach (t; 0 .. 2) { chmax(lbs[t], x); chmin(ubs[t], x); } } foreach (u; us) { if (vis[u][0]) { // x[u] = x[r] + val[u][0] foreach (t; 0 .. 2) { chmax(lbs[t], 1 - val[u][0]); chmin(ubs[t], (K - t) - val[u][0]); } } if (vis[u][1]) { // x[u] = -x[r] + val[u][1] foreach (t; 0 .. 2) { chmax(lbs[t], val[u][1] - (K - t)); chmin(ubs[t], val[u][1] - 1); } } } foreach (t; 0 .. 2) { debug { writefln(" t = %s: [%s, %s]", t, lbs[t], ubs[t]); } anss[t] *= max(ubs[t] - lbs[t] + 1, 0); } } failed: } const ans = anss[0] - anss[1]; writeln(ans); } } catch (EOFException e) { } }