#include <bits/stdc++.h>
using namespace std;
#define rep(i, a, b) for (int i = (a); i < (b); i++)
#define all(x) begin(x), end(x)
#define sz(x) int((x).size())
using ll = long long;
using pii = pair<int, int>;
using vi = vector<int>;
#ifdef LOCAL
auto operator<<(auto& o, auto x) -> decltype(x.first, o);
auto operator<<(auto& o, auto x) -> decltype(x.end(), o) {
o << "{";
for (int i = 0; auto y : x) o << ", " + !i++ * 2 << y;
return o << "}"; }
auto operator<<(auto& o, auto x) -> decltype(x.first, o) {
return o << "(" << x.first << ", " << x.second << ")"; }
void __print(auto... x) { ((cerr << x << " "), ...) << endl; }
#define debug(x...) __print("[" #x "]:", x)
#else
#define debug(...) 2137
#endif
const int N = 101;
const int S = 32000;
using A = array<int, 3>;
int n, m;
int p[N];
vector<pii> g[N], r[N];
bool vis[N][S];
int dp[N][S];
void dfs(int u, int x) {
vis[u][x] = 1;
for (auto [v, w] : g[u]) {
ll y = 1ll * x * w;
if (y < S && y <= p[v] && !vis[v][y]) {
dfs(v, y);
}
}
}
bool cmp(const A& a, const A& b) {
if (a[0] != b[0]) return a[0] < b[0];
return 0;
}
void solve() {
cin >> n >> m;
rep(i, 0, n) {
g[i].clear();
r[i].clear();
rep(j, 0, S) {
vis[i][j] = 0;
dp[i][j] = -1;
}
}
rep(i, 0, n) cin >> p[i];
rep(i, 0, m) {
int u, v, w;
cin >> u >> v >> w;
u--; v--;
g[u].push_back({v, w});
r[v].push_back({u, w});
}
dfs(0, 1);
priority_queue<A, vector<A>, decltype(&cmp)> q(cmp);
dp[n - 1][1] = p[n - 1];
q.push({p[n - 1], n - 1, 1});
while (sz(q)) {
auto [d, u, x] = q.top(); q.pop();
if (d != dp[u][x]) continue;
for (auto [v, w] : r[u]) {
ll y = 1ll * x * w;
int d2 = min(p[v], d / w);
if (y < S && d2 > dp[v][y]) {
dp[v][y] = d2;
q.push({dp[v][y], v, y});
}
}
}
int odp = -1;
rep(i, 0, n) for (int j = S - 2; j >= 0; j--) dp[i][j] = max(dp[i][j], dp[i][j + 1]);
rep(i, 0, n) for (auto [j, w] : g[i]) {
int l = S - 1;
rep(k, 0, S) if (vis[i][k]) {
while (l > 0 && dp[j][l] < 1ll * k * w) l--;
if (dp[j][l] >= 1ll * k * w) odp = max(odp, k * w * l);
}
}
rep(i, 0, S) if (vis[n - 1][i]) odp = max(odp, i);
cout << odp << '\n';
}
int main() {
cin.tie(0)->sync_with_stdio(0);
int t;
cin >> t;
while (t--) solve();
}
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 | #include <bits/stdc++.h> using namespace std; #define rep(i, a, b) for (int i = (a); i < (b); i++) #define all(x) begin(x), end(x) #define sz(x) int((x).size()) using ll = long long; using pii = pair<int, int>; using vi = vector<int>; #ifdef LOCAL auto operator<<(auto& o, auto x) -> decltype(x.first, o); auto operator<<(auto& o, auto x) -> decltype(x.end(), o) { o << "{"; for (int i = 0; auto y : x) o << ", " + !i++ * 2 << y; return o << "}"; } auto operator<<(auto& o, auto x) -> decltype(x.first, o) { return o << "(" << x.first << ", " << x.second << ")"; } void __print(auto... x) { ((cerr << x << " "), ...) << endl; } #define debug(x...) __print("[" #x "]:", x) #else #define debug(...) 2137 #endif const int N = 101; const int S = 32000; using A = array<int, 3>; int n, m; int p[N]; vector<pii> g[N], r[N]; bool vis[N][S]; int dp[N][S]; void dfs(int u, int x) { vis[u][x] = 1; for (auto [v, w] : g[u]) { ll y = 1ll * x * w; if (y < S && y <= p[v] && !vis[v][y]) { dfs(v, y); } } } bool cmp(const A& a, const A& b) { if (a[0] != b[0]) return a[0] < b[0]; return 0; } void solve() { cin >> n >> m; rep(i, 0, n) { g[i].clear(); r[i].clear(); rep(j, 0, S) { vis[i][j] = 0; dp[i][j] = -1; } } rep(i, 0, n) cin >> p[i]; rep(i, 0, m) { int u, v, w; cin >> u >> v >> w; u--; v--; g[u].push_back({v, w}); r[v].push_back({u, w}); } dfs(0, 1); priority_queue<A, vector<A>, decltype(&cmp)> q(cmp); dp[n - 1][1] = p[n - 1]; q.push({p[n - 1], n - 1, 1}); while (sz(q)) { auto [d, u, x] = q.top(); q.pop(); if (d != dp[u][x]) continue; for (auto [v, w] : r[u]) { ll y = 1ll * x * w; int d2 = min(p[v], d / w); if (y < S && d2 > dp[v][y]) { dp[v][y] = d2; q.push({dp[v][y], v, y}); } } } int odp = -1; rep(i, 0, n) for (int j = S - 2; j >= 0; j--) dp[i][j] = max(dp[i][j], dp[i][j + 1]); rep(i, 0, n) for (auto [j, w] : g[i]) { int l = S - 1; rep(k, 0, S) if (vis[i][k]) { while (l > 0 && dp[j][l] < 1ll * k * w) l--; if (dp[j][l] >= 1ll * k * w) odp = max(odp, k * w * l); } } rep(i, 0, S) if (vis[n - 1][i]) odp = max(odp, i); cout << odp << '\n'; } int main() { cin.tie(0)->sync_with_stdio(0); int t; cin >> t; while (t--) solve(); } |
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