#pragma GCC optimize ("Ofast") #define _USE_MATH_DEFINES #include <bits/stdc++.h> #define FOR(i, a, b) for (auto i=(a); i<(b); i++) #define FORD(i, a, b) for (int i=(a); i>(b); i--) #define SZ(x) ((int)(x).size()) #define ALL(x) (x).begin(), (x).end() #define PPC(x) __builtin_popcountll(x) #define MSB(x) (63 - __builtin_clzll(x)) #define LSB(x) __builtin_ctzll(x) #define ARG(x, i) (get<i>(x)) #define ithBit(m, i) ((m) >> (i) & 1) #define pb push_back #define ft first #define sd second #define kw(a) ((a) * (a)) #define CLR(x) x.clear(), x.shrink_to_fit() #ifdef DEBUG #include "debug.h" #else #define dbg(...) 0 #endif using namespace std; template <typename T1, typename T2> inline void remin(T1& a, T2 b) { a = min(a, (T1)b); } template <typename T1, typename T2> inline void remax(T1& a, T2 b) { a = max(a, (T1)b); } const int maxN = 30'003; int vis[maxN], visCtr; vector <pair <int, int> > adding, removing; struct Graph { vector <int> G[maxN]; int order[maxN]; set <pair <int, int> > S; int n; void load(int _n, int m) { n = _n; while (m--) { int a, b; scanf ("%d%d", &a, &b); G[a].pb(b); G[b].pb(a); if (a > b) swap(a, b); if (a != 1) S.insert({ a, b }); } } void genOrder() { vis[1] = ++visCtr; order[0] = 1; for (int front = 0, back = 1; back < n; front++) { int v = order[front]; for (int u : G[v]) if (vis[u] != visCtr) vis[u] = visCtr, order[back++] = u; } } void addRootEdges() { int skip = SZ(G[1]) + 1; FOR(i, skip, n) { int v = order[i]; adding.pb({ 1, v }); } } void removeRootEdges() { int skip = SZ(G[1]) + 1; FORD(i, n-1, skip-1) { int v = order[i]; removing.pb({ 1, v }); } } }src, trg; void addAndRemoveEdges() { const auto& A = src.S; const auto& B = trg.S; auto at = A.begin(); auto bt = B.begin(); while (at != A.end() and bt != B.end()) { auto ord = *at <=> *bt; if (ord < 0) removing.pb(*at++); if (ord == 0) at++, bt++; if (ord > 0) adding.pb(*bt++); } while (at != A.end()) removing.pb(*at++); while (bt != B.end()) adding.pb(*bt++); } void print() { printf("%d\n", SZ(adding) + SZ(removing)); for (auto& [a, b] : adding) printf("+ %d %d\n", a, b); for (auto& [a, b] : removing) printf("- %d %d\n", a, b); printf("\n"); } void solve() { int n, m; scanf ("%d%d", &n, &m); src.load(n, m); scanf ("%d", &m); trg.load(n, m); src.genOrder(); src.addRootEdges(); addAndRemoveEdges(); trg.genOrder(); trg.removeRootEdges(); print(); } int main() { int t = 1; // scanf ("%d", &t); FOR(tid, 1, t+1) { //printf("Case #%d: ", tid); solve(); } 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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 | #pragma GCC optimize ("Ofast") #define _USE_MATH_DEFINES #include <bits/stdc++.h> #define FOR(i, a, b) for (auto i=(a); i<(b); i++) #define FORD(i, a, b) for (int i=(a); i>(b); i--) #define SZ(x) ((int)(x).size()) #define ALL(x) (x).begin(), (x).end() #define PPC(x) __builtin_popcountll(x) #define MSB(x) (63 - __builtin_clzll(x)) #define LSB(x) __builtin_ctzll(x) #define ARG(x, i) (get<i>(x)) #define ithBit(m, i) ((m) >> (i) & 1) #define pb push_back #define ft first #define sd second #define kw(a) ((a) * (a)) #define CLR(x) x.clear(), x.shrink_to_fit() #ifdef DEBUG #include "debug.h" #else #define dbg(...) 0 #endif using namespace std; template <typename T1, typename T2> inline void remin(T1& a, T2 b) { a = min(a, (T1)b); } template <typename T1, typename T2> inline void remax(T1& a, T2 b) { a = max(a, (T1)b); } const int maxN = 30'003; int vis[maxN], visCtr; vector <pair <int, int> > adding, removing; struct Graph { vector <int> G[maxN]; int order[maxN]; set <pair <int, int> > S; int n; void load(int _n, int m) { n = _n; while (m--) { int a, b; scanf ("%d%d", &a, &b); G[a].pb(b); G[b].pb(a); if (a > b) swap(a, b); if (a != 1) S.insert({ a, b }); } } void genOrder() { vis[1] = ++visCtr; order[0] = 1; for (int front = 0, back = 1; back < n; front++) { int v = order[front]; for (int u : G[v]) if (vis[u] != visCtr) vis[u] = visCtr, order[back++] = u; } } void addRootEdges() { int skip = SZ(G[1]) + 1; FOR(i, skip, n) { int v = order[i]; adding.pb({ 1, v }); } } void removeRootEdges() { int skip = SZ(G[1]) + 1; FORD(i, n-1, skip-1) { int v = order[i]; removing.pb({ 1, v }); } } }src, trg; void addAndRemoveEdges() { const auto& A = src.S; const auto& B = trg.S; auto at = A.begin(); auto bt = B.begin(); while (at != A.end() and bt != B.end()) { auto ord = *at <=> *bt; if (ord < 0) removing.pb(*at++); if (ord == 0) at++, bt++; if (ord > 0) adding.pb(*bt++); } while (at != A.end()) removing.pb(*at++); while (bt != B.end()) adding.pb(*bt++); } void print() { printf("%d\n", SZ(adding) + SZ(removing)); for (auto& [a, b] : adding) printf("+ %d %d\n", a, b); for (auto& [a, b] : removing) printf("- %d %d\n", a, b); printf("\n"); } void solve() { int n, m; scanf ("%d%d", &n, &m); src.load(n, m); scanf ("%d", &m); trg.load(n, m); src.genOrder(); src.addRootEdges(); addAndRemoveEdges(); trg.genOrder(); trg.removeRootEdges(); print(); } int main() { int t = 1; // scanf ("%d", &t); FOR(tid, 1, t+1) { //printf("Case #%d: ", tid); solve(); } return 0; } |