#include <bits/stdc++.h> using namespace std; #ifdef LOCAL #include "debug.h" #else #define debug(...) #endif #define x first #define y second #define ir(a, x, b) ((a) <= (x) && (x) <= (b)) #define vec vector #define rep(i, a, b) for (int i = a; i < (b); ++i) #define all(x) (x).begin(), (x).end() using ll = long long; int n; vec<bool> conn, vis; vec<pair<bool, pair<int, int>>> ops, ops2; vec<pair<int, int>> edges; vec<vec<int>> g; void add(int a, int b) { ops.push_back({true, {a, b}}); } void rem(int a, int b) { ops.push_back({false, {a, b}}); } void dfs(int v, int p, int omit) { if (vis[v]) return; vis[v] = true; if (omit <= 0 && !conn[v]) { add(0, v); } for (auto c : g[v]) { if (c == p) continue; dfs(c, v, omit-1); } } void solve() { int m; cin >> m; conn.assign(n, 0); edges.clear(); edges.reserve(m); g.assign(n, {}); vis.assign(n, false); rep (i, 0, m) { int a, b; cin >> a >> b; --a, --b; g[a].push_back(b); g[b].push_back(a); if (a == 0) conn[b] = true; if (b == 0) conn[a] = true; edges.push_back({a, b}); } dfs(0, 0, 2); for (auto [a, b] : edges) { if (a != 0 && b != 0) { rem(a, b); } } } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n; solve(); swap(ops, ops2); solve(); swap(ops, ops2); cout << ops.size() + ops2.size() << "\n"; for (auto [op, e] : ops) { auto [a, b] = e; cout << (op?'+':'-') << " " << a+1 << " " << b+1 << "\n"; } reverse(all(ops2)); for (auto [op, e] : ops2) { auto [a, b] = e; cout << (op?'-':'+') << " " << a+1 << " " << b+1 << "\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 | #include <bits/stdc++.h> using namespace std; #ifdef LOCAL #include "debug.h" #else #define debug(...) #endif #define x first #define y second #define ir(a, x, b) ((a) <= (x) && (x) <= (b)) #define vec vector #define rep(i, a, b) for (int i = a; i < (b); ++i) #define all(x) (x).begin(), (x).end() using ll = long long; int n; vec<bool> conn, vis; vec<pair<bool, pair<int, int>>> ops, ops2; vec<pair<int, int>> edges; vec<vec<int>> g; void add(int a, int b) { ops.push_back({true, {a, b}}); } void rem(int a, int b) { ops.push_back({false, {a, b}}); } void dfs(int v, int p, int omit) { if (vis[v]) return; vis[v] = true; if (omit <= 0 && !conn[v]) { add(0, v); } for (auto c : g[v]) { if (c == p) continue; dfs(c, v, omit-1); } } void solve() { int m; cin >> m; conn.assign(n, 0); edges.clear(); edges.reserve(m); g.assign(n, {}); vis.assign(n, false); rep (i, 0, m) { int a, b; cin >> a >> b; --a, --b; g[a].push_back(b); g[b].push_back(a); if (a == 0) conn[b] = true; if (b == 0) conn[a] = true; edges.push_back({a, b}); } dfs(0, 0, 2); for (auto [a, b] : edges) { if (a != 0 && b != 0) { rem(a, b); } } } int main() { ios::sync_with_stdio(0); cin.tie(0); cout.tie(0); cin >> n; solve(); swap(ops, ops2); solve(); swap(ops, ops2); cout << ops.size() + ops2.size() << "\n"; for (auto [op, e] : ops) { auto [a, b] = e; cout << (op?'+':'-') << " " << a+1 << " " << b+1 << "\n"; } reverse(all(ops2)); for (auto [op, e] : ops2) { auto [a, b] = e; cout << (op?'-':'+') << " " << a+1 << " " << b+1 << "\n"; } return 0; } |