// clang-format off
#include <bits/stdc++.h>
using namespace std;
#define ALL(x) (x).begin(), (x).end()
template<class C> void mini(C &a5, C b5) { a5 = min(a5, b5); }
template<class C> void maxi(C &a5, C b5) { a5 = max(a5, b5); }
#ifdef LOCAL
const bool debug = true;
#else
const bool debug = false;
#define cerr if (true) {} else cout
#endif
// clang-format on
#define int long long
#define double long double
const int INF = 1e18;
const int mod = 1e9 + 7;
const int NAX = 110;
const int IAX = 32000;
bool dp[NAX][IAX];
int dk[NAX][IAX];
int dp2[NAX][IAX];
int p[NAX];
struct Edge {
int u, v, w;
};
vector<Edge> edges;
struct QueueNode {
int u, iloczyn, lim;
bool operator<(const QueueNode &other) const {
if (iloczyn == other.iloczyn)
return lim > other.lim;
return iloczyn < other.iloczyn;
}
void print() { cout << u << " " << iloczyn << " " << lim << "\n"; }
};
void dfs_dp(int n) {
dp[1][1] = true;
vector<vector<pair<int, int>>> drogi(n + 10);
for (Edge &edge : edges)
drogi[edge.u].push_back({edge.v, edge.w});
priority_queue<QueueNode> q;
q.push({1, 1, true});
while (!q.empty()) {
QueueNode curr = q.top();
q.pop();
for (auto [v, w] : drogi[curr.u]) {
QueueNode candidate = {v, curr.iloczyn * w, true};
if (candidate.iloczyn >= IAX || candidate.iloczyn > p[v])
continue;
if (dp[v][candidate.iloczyn] == false) {
dp[v][candidate.iloczyn] = true;
q.push(candidate);
}
}
}
}
void dfs_dk(int n) {
dk[n][1] = p[n];
vector<vector<pair<int, int>>> drogi(n + 10);
for (Edge &edge : edges)
drogi[edge.v].push_back({edge.u, edge.w});
priority_queue<QueueNode> q;
q.push({n, 1, p[n]});
while (!q.empty()) {
QueueNode curr = q.top();
q.pop();
if (dk[curr.u][curr.iloczyn] != curr.lim)
continue;
for (auto [v, w] : drogi[curr.u]) {
QueueNode candidate = {v, curr.iloczyn * w,
min(curr.lim / w, p[v])};
if (candidate.iloczyn >= IAX)
continue;
if (dk[v][candidate.iloczyn] < candidate.lim) {
dk[v][candidate.iloczyn] = candidate.lim;
q.push(candidate);
}
}
}
}
void debug_print(int n) {
cout << "dp:\n";
for (int i = 1; i <= n; i++) {
cout << i << ": ";
for (int ilo = 1; ilo < IAX; ilo++)
if (dp[i][ilo])
cout << ilo << "," << dp[i][ilo] << " ";
cout << "\n";
}
cout << "dk:\n";
for (int i = 1; i <= n; i++) {
cout << i << ": ";
for (int ilo = 1; ilo < IAX; ilo++)
if (dk[i][ilo])
cout << ilo << "," << dk[i][ilo] << " ";
cout << "\n";
}
cout << "dp2:\n";
for (int i = 1; i <= n; i++) {
cout << i << ": ";
for (int ilo = 1; ilo < IAX; ilo++)
if (dp2[i][ilo])
cout << ilo << "," << dp2[i][ilo] << " ";
cout << "\n";
}
cout << "\n";
}
void solve() {
edges.clear();
int n, m;
cin >> n >> m;
for (int i = 1; i <= n; i++)
cin >> p[i];
for (int i = 0; i < m; i++) {
int u, v, w;
cin >> u >> v >> w;
edges.push_back({u, v, w});
}
for (int i = 0; i <= n; i++)
for (int j = 0; j < IAX; j++)
dp[i][j] = dk[i][j] = dp2[i][j] = 0;
dfs_dp(n);
dfs_dk(n);
for (int u = 1; u <= n; u++)
for (int ilo = 1; ilo < IAX; ilo++)
if (dp[u][ilo])
dp2[u][ilo] = ilo;
else
dp2[u][ilo] = dp2[u][ilo - 1];
// debug_print(n);
int res = 0;
if (dp[n][1])
res = 1;
for (Edge &edge : edges)
for (int ilo = 1; ilo < IAX; ilo++) {
int ilo_p = min(dk[edge.v][ilo] / edge.w, IAX - 1);
ilo_p = dp2[edge.u][ilo_p];
maxi(res, ilo_p * edge.w * ilo);
}
if (res == 0)
res = -1;
cout << res << "\n";
}
int32_t main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
int t;
cin >> t;
while (t--) {
solve();
}
return 0;
} /*
*/
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 | // clang-format off #include <bits/stdc++.h> using namespace std; #define ALL(x) (x).begin(), (x).end() template<class C> void mini(C &a5, C b5) { a5 = min(a5, b5); } template<class C> void maxi(C &a5, C b5) { a5 = max(a5, b5); } #ifdef LOCAL const bool debug = true; #else const bool debug = false; #define cerr if (true) {} else cout #endif // clang-format on #define int long long #define double long double const int INF = 1e18; const int mod = 1e9 + 7; const int NAX = 110; const int IAX = 32000; bool dp[NAX][IAX]; int dk[NAX][IAX]; int dp2[NAX][IAX]; int p[NAX]; struct Edge { int u, v, w; }; vector<Edge> edges; struct QueueNode { int u, iloczyn, lim; bool operator<(const QueueNode &other) const { if (iloczyn == other.iloczyn) return lim > other.lim; return iloczyn < other.iloczyn; } void print() { cout << u << " " << iloczyn << " " << lim << "\n"; } }; void dfs_dp(int n) { dp[1][1] = true; vector<vector<pair<int, int>>> drogi(n + 10); for (Edge &edge : edges) drogi[edge.u].push_back({edge.v, edge.w}); priority_queue<QueueNode> q; q.push({1, 1, true}); while (!q.empty()) { QueueNode curr = q.top(); q.pop(); for (auto [v, w] : drogi[curr.u]) { QueueNode candidate = {v, curr.iloczyn * w, true}; if (candidate.iloczyn >= IAX || candidate.iloczyn > p[v]) continue; if (dp[v][candidate.iloczyn] == false) { dp[v][candidate.iloczyn] = true; q.push(candidate); } } } } void dfs_dk(int n) { dk[n][1] = p[n]; vector<vector<pair<int, int>>> drogi(n + 10); for (Edge &edge : edges) drogi[edge.v].push_back({edge.u, edge.w}); priority_queue<QueueNode> q; q.push({n, 1, p[n]}); while (!q.empty()) { QueueNode curr = q.top(); q.pop(); if (dk[curr.u][curr.iloczyn] != curr.lim) continue; for (auto [v, w] : drogi[curr.u]) { QueueNode candidate = {v, curr.iloczyn * w, min(curr.lim / w, p[v])}; if (candidate.iloczyn >= IAX) continue; if (dk[v][candidate.iloczyn] < candidate.lim) { dk[v][candidate.iloczyn] = candidate.lim; q.push(candidate); } } } } void debug_print(int n) { cout << "dp:\n"; for (int i = 1; i <= n; i++) { cout << i << ": "; for (int ilo = 1; ilo < IAX; ilo++) if (dp[i][ilo]) cout << ilo << "," << dp[i][ilo] << " "; cout << "\n"; } cout << "dk:\n"; for (int i = 1; i <= n; i++) { cout << i << ": "; for (int ilo = 1; ilo < IAX; ilo++) if (dk[i][ilo]) cout << ilo << "," << dk[i][ilo] << " "; cout << "\n"; } cout << "dp2:\n"; for (int i = 1; i <= n; i++) { cout << i << ": "; for (int ilo = 1; ilo < IAX; ilo++) if (dp2[i][ilo]) cout << ilo << "," << dp2[i][ilo] << " "; cout << "\n"; } cout << "\n"; } void solve() { edges.clear(); int n, m; cin >> n >> m; for (int i = 1; i <= n; i++) cin >> p[i]; for (int i = 0; i < m; i++) { int u, v, w; cin >> u >> v >> w; edges.push_back({u, v, w}); } for (int i = 0; i <= n; i++) for (int j = 0; j < IAX; j++) dp[i][j] = dk[i][j] = dp2[i][j] = 0; dfs_dp(n); dfs_dk(n); for (int u = 1; u <= n; u++) for (int ilo = 1; ilo < IAX; ilo++) if (dp[u][ilo]) dp2[u][ilo] = ilo; else dp2[u][ilo] = dp2[u][ilo - 1]; // debug_print(n); int res = 0; if (dp[n][1]) res = 1; for (Edge &edge : edges) for (int ilo = 1; ilo < IAX; ilo++) { int ilo_p = min(dk[edge.v][ilo] / edge.w, IAX - 1); ilo_p = dp2[edge.u][ilo_p]; maxi(res, ilo_p * edge.w * ilo); } if (res == 0) res = -1; cout << res << "\n"; } int32_t main() { ios_base::sync_with_stdio(0); cin.tie(0); int t; cin >> t; while (t--) { solve(); } return 0; } /* */ |
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