#include <bits/stdc++.h> using namespace std; using LL = long long; #define FOR(i, l, r) for(int i = (l); i <= (r); ++i) #define REP(i, n) FOR(i, 0, (n) - 1) #define ssize(x) int(x.size()) template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) { return o << '(' << p.first << ", " << p.second << ')'; } template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) { o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e; return o << '}'; } #ifdef DEBUG #define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n'; #else #define debug(...) {} #endif vector<vector<int>> va, vb; vector<bool> visited; vector<pair<bool, pair<int, int>>> ans; map<pair<int, int>, bool> edges_a, edges_b; void dfs(int x) { visited[x] = true; for (auto &y : va[x]) { if (!visited[y]) { if (!edges_a[{1, y}]) ans.push_back({true, {1, y}}); dfs(y); } } } void dfs2(int x) { visited[x] = false; for (auto &y : vb[x]) { if (visited[y]) { dfs2(y); if (!edges_b[{1, y}]) ans.push_back({false, {1, y}}); } } } int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int n, m1, m2; cin >> n >> m1; va.resize(n + 1); vb.resize(n + 1); visited.resize(n + 1); REP(i, m1) { int x, y; cin >> x >> y; if (x > y) swap(x, y); va[x].emplace_back(y); va[y].emplace_back(x); edges_a[{x, y}] = true; } dfs(1); for (auto &[p, ex] : edges_a) { auto &[x, y] = p; if (ex && x != 1) ans.push_back({false, {x, y}}); } cin >> m2; REP(i, m2) { int x, y; cin >> x >> y; if (x > y) swap(x, y); if (x != 1) ans.push_back({true, {x, y}}); vb[x].emplace_back(y); vb[y].emplace_back(x); edges_b[{x, y}] = true; } dfs2(1); cout << ssize(ans) << '\n'; for (auto &[tp, p] : ans) { auto &[x, y] = p; cout << (tp ? "+ " : "- "); cout << x << ' ' << y << '\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 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 | #include <bits/stdc++.h> using namespace std; using LL = long long; #define FOR(i, l, r) for(int i = (l); i <= (r); ++i) #define REP(i, n) FOR(i, 0, (n) - 1) #define ssize(x) int(x.size()) template<class A, class B> auto &operator<<(ostream &o, pair<A, B> p) { return o << '(' << p.first << ", " << p.second << ')'; } template<class T> auto operator<<(ostream &o, T x) -> decltype(x.end(), o) { o << '{'; int i = 0; for (auto e : x) o << (", ")+2*!i++ << e; return o << '}'; } #ifdef DEBUG #define debug(x...) cerr << "[" #x "]: ", [](auto... $) {((cerr << $ << "; "), ...); }(x), cerr << '\n'; #else #define debug(...) {} #endif vector<vector<int>> va, vb; vector<bool> visited; vector<pair<bool, pair<int, int>>> ans; map<pair<int, int>, bool> edges_a, edges_b; void dfs(int x) { visited[x] = true; for (auto &y : va[x]) { if (!visited[y]) { if (!edges_a[{1, y}]) ans.push_back({true, {1, y}}); dfs(y); } } } void dfs2(int x) { visited[x] = false; for (auto &y : vb[x]) { if (visited[y]) { dfs2(y); if (!edges_b[{1, y}]) ans.push_back({false, {1, y}}); } } } int main() { ios_base::sync_with_stdio(false); cin.tie(nullptr); int n, m1, m2; cin >> n >> m1; va.resize(n + 1); vb.resize(n + 1); visited.resize(n + 1); REP(i, m1) { int x, y; cin >> x >> y; if (x > y) swap(x, y); va[x].emplace_back(y); va[y].emplace_back(x); edges_a[{x, y}] = true; } dfs(1); for (auto &[p, ex] : edges_a) { auto &[x, y] = p; if (ex && x != 1) ans.push_back({false, {x, y}}); } cin >> m2; REP(i, m2) { int x, y; cin >> x >> y; if (x > y) swap(x, y); if (x != 1) ans.push_back({true, {x, y}}); vb[x].emplace_back(y); vb[y].emplace_back(x); edges_b[{x, y}] = true; } dfs2(1); cout << ssize(ans) << '\n'; for (auto &[tp, p] : ans) { auto &[x, y] = p; cout << (tp ? "+ " : "- "); cout << x << ' ' << y << '\n'; } return 0; } |