#include <cstdio> #include <cstdlib> #include <cstring> #include <vector> #include <set> using lli = long long int; struct connection_info { int to; lli amplification; }; struct vertex_info { lli max_throughput; std::vector<connection_info> connections; }; struct search_configuration { int at; lli strength; auto operator<=>(const search_configuration&) const = default; }; void do_single_case() { int n, m; scanf("%d %d\n", &n, &m); std::vector<vertex_info> vertices; for (int i = 0; i < n; i++) { int p; scanf("%d", &p); vertices.push_back(vertex_info{p, {}}); } for (int i = 0; i < m; i++) { int a, b; lli w; scanf("%d %d %lld", &a, &b, &w); a--; b--; vertices[a].connections.push_back(connection_info{b, w}); } lli best_seen = -1; std::set<search_configuration> visited_configs; std::vector<search_configuration> stack; stack.push_back({0, 1}); while (!stack.empty()) { auto state = stack.back(); stack.pop_back(); auto [it, inserted] = visited_configs.insert(state); if (!inserted) { // Was already visited - just continue continue; } if (state.at == n - 1 && best_seen < state.strength) { best_seen = state.strength; } for (const auto& conn : vertices[state.at].connections) { const lli new_strength = state.strength * conn.amplification; if (new_strength <= vertices[conn.to].max_throughput) { stack.push_back({conn.to, new_strength}); } } } printf("%lld\n", best_seen); } int main() { int t; scanf("%d\n", &t); while (t --> 0) { do_single_case(); } 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 | #include <cstdio> #include <cstdlib> #include <cstring> #include <vector> #include <set> using lli = long long int; struct connection_info { int to; lli amplification; }; struct vertex_info { lli max_throughput; std::vector<connection_info> connections; }; struct search_configuration { int at; lli strength; auto operator<=>(const search_configuration&) const = default; }; void do_single_case() { int n, m; scanf("%d %d\n", &n, &m); std::vector<vertex_info> vertices; for (int i = 0; i < n; i++) { int p; scanf("%d", &p); vertices.push_back(vertex_info{p, {}}); } for (int i = 0; i < m; i++) { int a, b; lli w; scanf("%d %d %lld", &a, &b, &w); a--; b--; vertices[a].connections.push_back(connection_info{b, w}); } lli best_seen = -1; std::set<search_configuration> visited_configs; std::vector<search_configuration> stack; stack.push_back({0, 1}); while (!stack.empty()) { auto state = stack.back(); stack.pop_back(); auto [it, inserted] = visited_configs.insert(state); if (!inserted) { // Was already visited - just continue continue; } if (state.at == n - 1 && best_seen < state.strength) { best_seen = state.strength; } for (const auto& conn : vertices[state.at].connections) { const lli new_strength = state.strength * conn.amplification; if (new_strength <= vertices[conn.to].max_throughput) { stack.push_back({conn.to, new_strength}); } } } printf("%lld\n", best_seen); } int main() { int t; scanf("%d\n", &t); while (t --> 0) { do_single_case(); } return 0; } |