#include <bits/stdc++.h> using namespace std; struct Triple { int sign, st, nd; Triple(int sign, int st, int nd) : sign(sign), st(st), nd(nd) {}; }; void dfs(vector<vector<int>> &graph, vector<bool> &vis, vector<int> &queue, set<pair<int, int>> &expected, int v) { if (vis[v]) return; vis[v] = true; for (auto w : graph[v]) { if (v == 1 && expected.find({v, w}) == expected.end()) continue; dfs(graph, vis, queue, expected, w); } if (v != 1) queue.push_back(v); } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n, m; cin >> n >> m; set<pair<int, int>> s; for (int i = 0; i < m; i++) { int v, w; cin >> v >> w; if (v > w) s.insert({w, v}); else s.insert({v, w}); } int m1; cin >> m1; set<pair<int, int>> expected; for (int i = 0; i < m1; i++) { int v, w; cin >> v >> w; if (v > w) expected.insert({w, v}); else expected.insert({v, w}); } vector<Triple> ans; for (int i = 2; i <= n; i++) { if (s.find({1, i}) == s.end()) { s.insert({1, i}); ans.push_back(Triple(1, 1, i)); } } for (auto elem : expected) { if (s.find(elem) == s.end()) { s.insert(elem); ans.push_back(Triple(1, elem.first, elem.second)); } } vector<pair<int, int>> toRemove; for (auto elem : s) { if (elem.first != 1 && expected.find(elem) == expected.end()) { toRemove.push_back(elem); ans.push_back(Triple(0, elem.first, elem.second)); } } for (auto elem : toRemove) s.erase(elem); vector<vector<int>> graph(n+1); for (auto elem : s) { graph[elem.first].push_back(elem.second); graph[elem.second].push_back(elem.first); } vector<int> queue; vector<bool> vis(n+1, false); dfs(graph, vis, queue, expected, 1); for (auto elem : queue) { if (expected.find({1, elem}) == expected.end()) ans.push_back(Triple(0, 1, elem)); } cout << ans.size() << "\n"; for (auto elem : ans) { cout << (elem.sign ? "+ " : "- ") << elem.st << " " << elem.nd << "\n"; } 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 | #include <bits/stdc++.h> using namespace std; struct Triple { int sign, st, nd; Triple(int sign, int st, int nd) : sign(sign), st(st), nd(nd) {}; }; void dfs(vector<vector<int>> &graph, vector<bool> &vis, vector<int> &queue, set<pair<int, int>> &expected, int v) { if (vis[v]) return; vis[v] = true; for (auto w : graph[v]) { if (v == 1 && expected.find({v, w}) == expected.end()) continue; dfs(graph, vis, queue, expected, w); } if (v != 1) queue.push_back(v); } int main() { ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); int n, m; cin >> n >> m; set<pair<int, int>> s; for (int i = 0; i < m; i++) { int v, w; cin >> v >> w; if (v > w) s.insert({w, v}); else s.insert({v, w}); } int m1; cin >> m1; set<pair<int, int>> expected; for (int i = 0; i < m1; i++) { int v, w; cin >> v >> w; if (v > w) expected.insert({w, v}); else expected.insert({v, w}); } vector<Triple> ans; for (int i = 2; i <= n; i++) { if (s.find({1, i}) == s.end()) { s.insert({1, i}); ans.push_back(Triple(1, 1, i)); } } for (auto elem : expected) { if (s.find(elem) == s.end()) { s.insert(elem); ans.push_back(Triple(1, elem.first, elem.second)); } } vector<pair<int, int>> toRemove; for (auto elem : s) { if (elem.first != 1 && expected.find(elem) == expected.end()) { toRemove.push_back(elem); ans.push_back(Triple(0, elem.first, elem.second)); } } for (auto elem : toRemove) s.erase(elem); vector<vector<int>> graph(n+1); for (auto elem : s) { graph[elem.first].push_back(elem.second); graph[elem.second].push_back(elem.first); } vector<int> queue; vector<bool> vis(n+1, false); dfs(graph, vis, queue, expected, 1); for (auto elem : queue) { if (expected.find({1, elem}) == expected.end()) ans.push_back(Triple(0, 1, elem)); } cout << ans.size() << "\n"; for (auto elem : ans) { cout << (elem.sign ? "+ " : "- ") << elem.st << " " << elem.nd << "\n"; } return 0; } |