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| #include <bits/stdc++.h> using namespace std;
const int N = 100004; struct E {int nxt, v, w;} e1[N << 1], e2[N << 1]; int n, m, head1[N], dis1[N], head2[N], dis2[N], ecnt1, ecnt2, k, MOD, qp[N], tot, d[N], f[55][N]; queue<int> q; bool book[N];
void add-edge(int u, int v, int w) { e1[++ecnt1] = {head1[u], v, w}; head1[u] = ecnt1; e2[++ecnt2] = {head2[v], u, w}; head2[v] = ecnt2; }
void upd(int &x, int y) { x = x + y; if (x >= MOD) x -= MOD; }
void solve() { ecnt1 = ecnt2 = 0; memset(dis1, 0x3f, sizeof dis1); memset(dis2, 0x3f, sizeof dis2); memset(head1, 0, sizeof head1); memset(head2, 0, sizeof head2); scanf("%d %d %d %d", &n, &m, &k, &MOD); for (int i = 1; i <= m; i++) { int u, v, w; scanf("%d %d %d", &u, &v, &w); add-edge(u, v, w); } priority-queue<pair<int, int> > q; dis1[1] = 0; memset(book, 0, sizeof book); q.push({0, 1}); while (!q.empty()) { int u = q.top().second; q.pop(); if (book[u]) continue; book[u] = 1; for (int i = head1[u]; i; i = e1[i].nxt) { int v = e1[i].v, w = e1[i].w; if (dis1[u] + w < dis1[v]) { dis1[v] = dis1[u] + w; q.push({-dis1[v], v}); } } } dis2[n] = 0; memset(book, 0, sizeof book); q.push({0, n}); while (!q.empty()) { int u = q.top().second; q.pop(); if (book[u]) continue; book[u] = 1; for (int i = head2[u]; i; i = e2[i].nxt) { int v = e2[i].v, w = e2[i].w; if (dis2[u] + w < dis2[v]) { dis2[v] = dis2[u] + w; q.push({-dis2[v], v}); } } } memset(d, 0, sizeof d); tot = 0; for (int i = 1; i <= n; i++) for (int j = head1[i]; j; j = e1[j].nxt) { int v = e1[j].v, w = e1[j].w; if (dis1[i] + w == dis1[v]) d[v]++; } for (int i = 1; i <= n; i++) if (d[i] == 0) qp[++tot] = i; for (int i = 1; i <= tot; i++) { int u = qp[i]; for (int j = head1[u]; j; j = e1[j].nxt) { int v = e1[j].v, w = e1[j].w; if (dis1[v] == dis1[u] + w) { d[v]--; if (d[v] == 0) qp[++tot] = v; } } } for (int i = 1; i <= n; i++) { if (d[i] && dis1[i] + dis2[i] <= dis1[n] + k) { puts("-1"); return; } } memset(f, 0, sizeof f); f[0][1] = 1; for (int l = 0; l <= k; l++) { for (int i = 1; i <= tot; i++) { int u = qp[i]; for (int j = head1[u]; j; j = e1[j].nxt) { int v = e1[j].v, w = e1[j].w; if (dis1[v] == dis1[u] + w) upd(f[l][v], f[l][u]); } } for (int u = 1; u <= n; u++) { for (int j = head1[u]; j; j = e1[j].nxt) { int v = e1[j].v, w = e1[j].w; if (dis1[v] != dis1[u] + w && l + dis1[u] + w - dis1[v] <= k) { upd(f[l + dis1[u] + w - dis1[v]][v], f[l][u]); } } } } int res = 0; for (int i = 0; i <= k; i++) upd(res, f[i][n]); printf("%d\n", res); return; }
int main() { int -; for (scanf("%d", &-); -; ---) solve(); return 0; }
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