#include <algorithm> #include <iostream> #include <vector> class DisjointSetStructure { struct Element { int parent; int depth; }; Element* elements; public: DisjointSetStructure(size_t n) { elements = new Element[n]; while (n--) { elements[n].parent = n; elements[n].depth = 0; } } ~DisjointSetStructure() { delete[] elements; } int Find(int index) { int& parent = elements[index].parent; if (parent != index) parent = Find(parent); return parent; } void Union(int index1, int index2) { int root1index = Find(index1); int root2index = Find(index2); if (root1index != root2index) { Element& root1 = elements[root1index]; Element& root2 = elements[root2index]; if (root1.depth < root2.depth) { root1.parent = root2index; } else { root1.depth += root1.depth == root2.depth; root2.parent = root1index; } } } }; class Solver { std::vector<std::vector<int>> relT, relN; std::vector<int> parents; int total; bool fail; public: Solver(int n) : relT(n), relN(n), parents(n), total(n), fail(false) {} void Load(int m) { while (m--) { int a, b; char c; std::cin >> a >> b >> c; a--; b--; if (c == 'T') relT[a].push_back(b); else relN[b].push_back(a); } } void Solve(const std::vector<int>& nodes, int parent) { std::vector<int>::const_iterator root; { std::vector<int8_t> inNodes(total); for (const auto& node : nodes) { inNodes[node] = true; } auto inNodesFunc = [&](int other) { return inNodes[other]; }; root = std::find_if(nodes.begin(), nodes.end(), [&](int node) { return std::none_of(relT[node].begin(), relT[node].end(), inNodesFunc) && std::none_of(relN[node].begin(), relN[node].end(), inNodesFunc); }); } if (root == nodes.end()) { fail = true; } else { int rootNode = *root; parents[rootNode] = parent; std::vector<std::vector<int>> sets(total); { DisjointSetStructure dss(total); for (const auto& node : nodes) { if (node != rootNode) { for (const auto& other : relT[node]) { dss.Union(node, other); } } } for (const auto& node : nodes) { if (node != rootNode) sets[dss.Find(node)].push_back(node); } } for (const auto& s : sets) { if (!s.empty()) { Solve(s, rootNode); if (fail) break; } } } } void Write() const { if (fail) { std::cout << "NIE\n"; } else { for (const auto& parent : parents) { std::cout << (parent + 1) << '\n'; } } } }; int main() { std::ios_base::sync_with_stdio(false); int n, m; std::cin >> n >> m; Solver solver(n); solver.Load(m); std::vector<int> allNodes(n); for (int i = n; i--;) { allNodes[i] = i; } solver.Solve(allNodes, -1); solver.Write(); 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 | #include <algorithm> #include <iostream> #include <vector> class DisjointSetStructure { struct Element { int parent; int depth; }; Element* elements; public: DisjointSetStructure(size_t n) { elements = new Element[n]; while (n--) { elements[n].parent = n; elements[n].depth = 0; } } ~DisjointSetStructure() { delete[] elements; } int Find(int index) { int& parent = elements[index].parent; if (parent != index) parent = Find(parent); return parent; } void Union(int index1, int index2) { int root1index = Find(index1); int root2index = Find(index2); if (root1index != root2index) { Element& root1 = elements[root1index]; Element& root2 = elements[root2index]; if (root1.depth < root2.depth) { root1.parent = root2index; } else { root1.depth += root1.depth == root2.depth; root2.parent = root1index; } } } }; class Solver { std::vector<std::vector<int>> relT, relN; std::vector<int> parents; int total; bool fail; public: Solver(int n) : relT(n), relN(n), parents(n), total(n), fail(false) {} void Load(int m) { while (m--) { int a, b; char c; std::cin >> a >> b >> c; a--; b--; if (c == 'T') relT[a].push_back(b); else relN[b].push_back(a); } } void Solve(const std::vector<int>& nodes, int parent) { std::vector<int>::const_iterator root; { std::vector<int8_t> inNodes(total); for (const auto& node : nodes) { inNodes[node] = true; } auto inNodesFunc = [&](int other) { return inNodes[other]; }; root = std::find_if(nodes.begin(), nodes.end(), [&](int node) { return std::none_of(relT[node].begin(), relT[node].end(), inNodesFunc) && std::none_of(relN[node].begin(), relN[node].end(), inNodesFunc); }); } if (root == nodes.end()) { fail = true; } else { int rootNode = *root; parents[rootNode] = parent; std::vector<std::vector<int>> sets(total); { DisjointSetStructure dss(total); for (const auto& node : nodes) { if (node != rootNode) { for (const auto& other : relT[node]) { dss.Union(node, other); } } } for (const auto& node : nodes) { if (node != rootNode) sets[dss.Find(node)].push_back(node); } } for (const auto& s : sets) { if (!s.empty()) { Solve(s, rootNode); if (fail) break; } } } } void Write() const { if (fail) { std::cout << "NIE\n"; } else { for (const auto& parent : parents) { std::cout << (parent + 1) << '\n'; } } } }; int main() { std::ios_base::sync_with_stdio(false); int n, m; std::cin >> n >> m; Solver solver(n); solver.Load(m); std::vector<int> allNodes(n); for (int i = n; i--;) { allNodes[i] = i; } solver.Solve(allNodes, -1); solver.Write(); return 0; } |