#include <bits/stdc++.h> const int MAX_N = 3e4; int n, m1, m2; std::vector<int> list[MAX_N + 3]; std::vector<int> list2[MAX_N + 3]; std::set<std::pair<int, int>> s1, s2; inline bool is_1(int x, int y) { return s1.count({x, y}) || s1.count({y, x}); } inline bool is_2(int x, int y) { return s2.count({x, y}) || s2.count({y, x}); } std::vector<std::pair<char, std::pair<int, int>>> R; void add_edge(int x, int y) { R.push_back({'+', {x, y}}); s1.insert({x, y}); } void remove_edge(int x, int y) { R.push_back({'-', {x, y}}); if (s1.count({x, y})) s1.erase({x, y}); if (s1.count({y, x})) s1.erase({y, x}); } std::vector<int> ord; bool visited[MAX_N + 3]; void dfs(int v) { visited[v] = true; ord.push_back(v); for (auto u : list[v]) if (!visited[u]) dfs(u); } void dfs2(int v) { visited[v] = true; ord.push_back(v); for (auto u : list2[v]) if (!visited[u]) dfs2(u); } int main() { std::ios_base::sync_with_stdio(0); std::cin.tie(NULL); std::cin >> n; std::cin >> m1; for (int i = 1; i <= m1; i++) { int u, v; std::cin >> u >> v; list[u].push_back(v); list[v].push_back(u); s1.insert({u, v}); } std::cin >> m2; for (int i = 1; i <= m2; i++) { int u, v; std::cin >> u >> v; list2[u].push_back(v); list2[v].push_back(u); s2.insert({u, v}); } for (int i = 1; i <= n; i++) visited[i] = false; dfs(1); // Add 1 to everyone - <= 30 000 ops for (int i = 1; i < n; i++) { int u = ord[i]; if (!is_1(1, u)) add_edge(1, u); } // Remove unnecessary in G[V \ {1}] - <= 50 000 ops std::vector<std::pair<int, int>> to_remove; for (auto &[x, y] : s1) { if (x != 1 && y != 1 && !is_2(x, y)) to_remove.push_back({x, y}); } for (auto &[x, y] : to_remove) remove_edge(x, y); // Add missing in G[V \ {1}] - <= 50 000 ops for (auto &[x, y] : s2) { if (x != 1 && y != 1 && !is_1(x, y)) add_edge(x, y); } ord.clear(); for (int i = 1; i <= n; i++) visited[i] = false; dfs2(1); // Remove unecessary incident to 1 - <= 30 000 ops for (int i = ord.size() - 1; i >= 1; i--) { int u = ord[i]; if (!is_2(1, u)) remove_edge(1, u); } std::cout << R.size() << "\n"; for (auto &[c, p] : R) std::cout << c << " " << p.first << " " << p.second << "\n"; }
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 | #include <bits/stdc++.h> const int MAX_N = 3e4; int n, m1, m2; std::vector<int> list[MAX_N + 3]; std::vector<int> list2[MAX_N + 3]; std::set<std::pair<int, int>> s1, s2; inline bool is_1(int x, int y) { return s1.count({x, y}) || s1.count({y, x}); } inline bool is_2(int x, int y) { return s2.count({x, y}) || s2.count({y, x}); } std::vector<std::pair<char, std::pair<int, int>>> R; void add_edge(int x, int y) { R.push_back({'+', {x, y}}); s1.insert({x, y}); } void remove_edge(int x, int y) { R.push_back({'-', {x, y}}); if (s1.count({x, y})) s1.erase({x, y}); if (s1.count({y, x})) s1.erase({y, x}); } std::vector<int> ord; bool visited[MAX_N + 3]; void dfs(int v) { visited[v] = true; ord.push_back(v); for (auto u : list[v]) if (!visited[u]) dfs(u); } void dfs2(int v) { visited[v] = true; ord.push_back(v); for (auto u : list2[v]) if (!visited[u]) dfs2(u); } int main() { std::ios_base::sync_with_stdio(0); std::cin.tie(NULL); std::cin >> n; std::cin >> m1; for (int i = 1; i <= m1; i++) { int u, v; std::cin >> u >> v; list[u].push_back(v); list[v].push_back(u); s1.insert({u, v}); } std::cin >> m2; for (int i = 1; i <= m2; i++) { int u, v; std::cin >> u >> v; list2[u].push_back(v); list2[v].push_back(u); s2.insert({u, v}); } for (int i = 1; i <= n; i++) visited[i] = false; dfs(1); // Add 1 to everyone - <= 30 000 ops for (int i = 1; i < n; i++) { int u = ord[i]; if (!is_1(1, u)) add_edge(1, u); } // Remove unnecessary in G[V \ {1}] - <= 50 000 ops std::vector<std::pair<int, int>> to_remove; for (auto &[x, y] : s1) { if (x != 1 && y != 1 && !is_2(x, y)) to_remove.push_back({x, y}); } for (auto &[x, y] : to_remove) remove_edge(x, y); // Add missing in G[V \ {1}] - <= 50 000 ops for (auto &[x, y] : s2) { if (x != 1 && y != 1 && !is_1(x, y)) add_edge(x, y); } ord.clear(); for (int i = 1; i <= n; i++) visited[i] = false; dfs2(1); // Remove unecessary incident to 1 - <= 30 000 ops for (int i = ord.size() - 1; i >= 1; i--) { int u = ord[i]; if (!is_2(1, u)) remove_edge(1, u); } std::cout << R.size() << "\n"; for (auto &[c, p] : R) std::cout << c << " " << p.first << " " << p.second << "\n"; } |