// Online C++ compiler to run C++ program online #include <iostream> #include <vector> #include <unordered_set> #include <queue> using namespace std; vector<vector<int>> res; void dodaj(int a, int b) { res.push_back({1, a+1, b+1}); } void odejmij(int a, int b) { res.push_back({-1, a+1, b+1}); } void zrob_gwiazde(int root, vector<unordered_set<int>>& v) { vector<bool> vis(v.size(), false); vis[root] = true; queue<pair<int, int>> q; // current node, parent q.push(make_pair(root, -1)); while(!q.empty()) { pair<int,int> top = q.front(); q.pop(); int node = top.first; int prev = top.second; if(prev != -1 && prev != root) { if(v[root].find(node) == v[root].end()) { v[root].insert(node); v[node].insert(root); dodaj(root, node); } } for(int neigh : v[node]) if(!vis[neigh]) { q.push(make_pair(neigh, node)); vis[neigh] = true; } } } void dfs(int root, int node, vector<unordered_set<int>>& v, vector<unordered_set<int>>& v2, vector<bool>& vis) { if(node == root) { for(int neigh : v2[root]) if(!vis[neigh]) { vis[neigh] = true; dfs(root, neigh, v, v2, vis); } } else { for(int neigh : v[node]) if(!vis[neigh]) { vis[neigh] = true; dfs(root, neigh, v, v2, vis); } } if(v[node].find(root) != v[node].end() && v2[node].find(root) == v2[node].end()) { v2[node].erase(root); v2[root].erase(node); odejmij(node, root); } } int main() { int n; cin >> n; vector<unordered_set<int>> v(n, unordered_set<int>()); int m; cin >> m; for(int i = 0; i < m; i++) { int a, b; cin >> a >> b; v[a-1].insert(b-1); v[b-1].insert(a-1); } int m2; cin >> m2; vector<unordered_set<int>> v2(n, unordered_set<int>()); for(int i = 0; i < m2; i++) { int a, b; cin >> a >> b; v2[a-1].insert(b-1); v2[b-1].insert(a-1); } int root = 0; zrob_gwiazde(root, v); // star // remove edges vector<unordered_set<int>> new_v(n, unordered_set<int>()); for(int i = 0; i < n; i++) { for(int j : v[i]) { if(i == root || j == root || v2[i].find(j) != v2[i].end()) { new_v[i].insert(j); } else { odejmij(i,j); v[j].erase(i); } } } v = new_v; // add edges for(int i = 0; i < n; i++) { for(int j : v2[i]) { if(v[i].find(j) == v[i].end()) { dodaj(i, j); v[i].insert(j); v[j].insert(i); } } } vector<bool> vis(n, false); vis[root] = true; dfs(root, root, v, v2, vis); cout << res.size() << endl; for(auto& r : res) { if(r[0] == 1) { cout << "+ "; } else { cout << "- "; } cout << r[1] << " " << r[2] << endl; } 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 | // Online C++ compiler to run C++ program online #include <iostream> #include <vector> #include <unordered_set> #include <queue> using namespace std; vector<vector<int>> res; void dodaj(int a, int b) { res.push_back({1, a+1, b+1}); } void odejmij(int a, int b) { res.push_back({-1, a+1, b+1}); } void zrob_gwiazde(int root, vector<unordered_set<int>>& v) { vector<bool> vis(v.size(), false); vis[root] = true; queue<pair<int, int>> q; // current node, parent q.push(make_pair(root, -1)); while(!q.empty()) { pair<int,int> top = q.front(); q.pop(); int node = top.first; int prev = top.second; if(prev != -1 && prev != root) { if(v[root].find(node) == v[root].end()) { v[root].insert(node); v[node].insert(root); dodaj(root, node); } } for(int neigh : v[node]) if(!vis[neigh]) { q.push(make_pair(neigh, node)); vis[neigh] = true; } } } void dfs(int root, int node, vector<unordered_set<int>>& v, vector<unordered_set<int>>& v2, vector<bool>& vis) { if(node == root) { for(int neigh : v2[root]) if(!vis[neigh]) { vis[neigh] = true; dfs(root, neigh, v, v2, vis); } } else { for(int neigh : v[node]) if(!vis[neigh]) { vis[neigh] = true; dfs(root, neigh, v, v2, vis); } } if(v[node].find(root) != v[node].end() && v2[node].find(root) == v2[node].end()) { v2[node].erase(root); v2[root].erase(node); odejmij(node, root); } } int main() { int n; cin >> n; vector<unordered_set<int>> v(n, unordered_set<int>()); int m; cin >> m; for(int i = 0; i < m; i++) { int a, b; cin >> a >> b; v[a-1].insert(b-1); v[b-1].insert(a-1); } int m2; cin >> m2; vector<unordered_set<int>> v2(n, unordered_set<int>()); for(int i = 0; i < m2; i++) { int a, b; cin >> a >> b; v2[a-1].insert(b-1); v2[b-1].insert(a-1); } int root = 0; zrob_gwiazde(root, v); // star // remove edges vector<unordered_set<int>> new_v(n, unordered_set<int>()); for(int i = 0; i < n; i++) { for(int j : v[i]) { if(i == root || j == root || v2[i].find(j) != v2[i].end()) { new_v[i].insert(j); } else { odejmij(i,j); v[j].erase(i); } } } v = new_v; // add edges for(int i = 0; i < n; i++) { for(int j : v2[i]) { if(v[i].find(j) == v[i].end()) { dodaj(i, j); v[i].insert(j); v[j].insert(i); } } } vector<bool> vis(n, false); vis[root] = true; dfs(root, root, v, v2, vis); cout << res.size() << endl; for(auto& r : res) { if(r[0] == 1) { cout << "+ "; } else { cout << "- "; } cout << r[1] << " " << r[2] << endl; } return 0; } |