結果
問題 | No.1436 Rgaph |
ユーザー | nok0 |
提出日時 | 2020-12-27 13:39:09 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 34 ms / 2,000 ms |
コード長 | 18,406 bytes |
コンパイル時間 | 3,140 ms |
コンパイル使用メモリ | 248,784 KB |
最終ジャッジ日時 | 2025-01-17 07:43:21 |
ジャッジサーバーID (参考情報) |
judge5 / judge3 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 2 |
other | AC * 28 |
コンパイルメッセージ
main.cpp: In function ‘void scan(char*)’: main.cpp:59:28: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result] 59 | void scan(char a[]) { scanf("%s", a); } | ~~~~~^~~~~~~~~
ソースコード
/*** author: nok0* created: 2020.11.07 23:37:48**/#ifdef LOCAL#define _GLIBCXX_DEBUG#endif#include <bits/stdc++.h>using namespace std;#pragma region Macros#define FOR(i, l, r) for(int i = (l); i < (r); ++i)#define REP(i, n) FOR(i, 0, n)#define REPS(i, n) FOR(i, 1, n + 1)#define RFOR(i, l, r) for(int i = (l); i >= (r); --i)#define RREP(i, n) RFOR(i, n - 1, 0)#define RREPS(i, n) RFOR(i, n, 1)#define pb push_back#define eb emplace_back#define SZ(x) ((int)(x).size())#define all(x) (x).begin(), (x).end()#define rall(x) (x).rbegin(), (x).rend()template <class T = int>using V = vector<T>;template <class T = int>using VV = V<V<T>>;using ll = long long;using ld = long double;using pii = pair<int, int>;using pll = pair<ll, ll>;#define VEC(type, name, size) \V<type> name(size); \INPUT(name)#define VVEC(type, name, h, w) \VV<type> name(h, V<type>(w)); \INPUT(name)#define INT(...) \int __VA_ARGS__; \INPUT(__VA_ARGS__)#define LL(...) \ll __VA_ARGS__; \INPUT(__VA_ARGS__)#define STR(...) \string __VA_ARGS__; \INPUT(__VA_ARGS__)#define CHAR(...) \char __VA_ARGS__; \INPUT(__VA_ARGS__)#define DOUBLE(...) \DOUBLE __VA_ARGS__; \INPUT(__VA_ARGS__)#define LD(...) \LD __VA_ARGS__; \INPUT(__VA_ARGS__)void scan(int &a) { cin >> a; }void scan(long long &a) { cin >> a; }void scan(char &a) { cin >> a; }void scan(double &a) { cin >> a; }void scan(long double &a) { cin >> a; }void scan(char a[]) { scanf("%s", a); }void scan(string &a) { cin >> a; }template <class T>void scan(V<T> &);template <class T, class L>void scan(pair<T, L> &);template <class T>void scan(V<T> &a) {for(auto &i : a) scan(i);}template <class T, class L>void scan(pair<T, L> &p) {scan(p.first);scan(p.second);}template <class T>void scan(T &a) { cin >> a; }void INPUT() {}template <class Head, class... Tail>void INPUT(Head &head, Tail &... tail) {scan(head);INPUT(tail...);}template <class T>inline void print(T x) { cout << x << '\n'; }template <class T>inline void dump(T x) {cout << x << '\n';exit(0);}template <typename T1, typename T2>istream &operator>>(istream &is, pair<T1, T2> &p) {is >> p.first >> p.second;return is;}template <typename T1, typename T2>ostream &operator<<(ostream &os, const pair<T1, T2> &p) {os << p.first << " " << p.second;return os;}template <typename T>istream &operator>>(istream &is, vector<T> &v) {for(T &in : v) is >> in;return is;}template <class T>ostream &operator<<(ostream &os, const V<T> &v) {REP(i, SZ(v)) {if(i) os << " ";os << v[i];}return os;}//debugtemplate <typename T>void view(const V<T> &v) {cerr << "{ ";for(const auto &e : v) {cerr << e << ", ";}cerr << "\b\b }";}template <typename T>void view(const VV<T> &vv) {cerr << "{\n";for(const auto &v : vv) {cerr << "\t";view(v);cerr << "\n";}cerr << "}";}template <typename T, typename U>void view(const V<pair<T, U>> &v) {cerr << "{\n";for(const auto &c : v) cerr << "\t(" << c.first << ", " << c.second << ")\n";cerr << "}";}template <typename T, typename U>void view(const map<T, U> &m) {cerr << "{\n";for(auto &t : m) cerr << "\t[" << t.first << "] : " << t.second << "\n";cerr << "}";}template <typename T, typename U>void view(const pair<T, U> &p) { cerr << "(" << p.first << ", " << p.second << ")"; }template <typename T>void view(const set<T> &s) {cerr << "{ ";for(auto &t : s) {view(t);cerr << ", ";}cerr << "\b\b }";}template <typename T>void view(T e) { cerr << e; }#ifdef LOCALvoid debug_out() {}template <typename Head, typename... Tail>void debug_out(Head H, Tail... T) {view(H);cerr << ", ";debug_out(T...);}#define debug(...) \do { \cerr << __LINE__ << " [" << #__VA_ARGS__ << "] : ["; \debug_out(__VA_ARGS__); \cerr << "\b\b]\n"; \} while(0)#else#define debug(...) (void(0))#endiftemplate <class T>V<T> press(V<T> &x) {V<T> res = x;sort(all(res));res.erase(unique(all(res)), res.end());REP(i, SZ(x)) {x[i] = lower_bound(all(res), x[i]) - res.begin();}return res;}template <class T>inline bool chmin(T &a, T b) {if(a > b) {a = b;return true;}return false;}template <class T>inline bool chmax(T &a, T b) {if(a < b) {a = b;return true;}return false;}inline void Yes(bool b = true) { cout << (b ? "Yes" : "No") << '\n'; }inline void YES(bool b = true) { cout << (b ? "YES" : "NO") << '\n'; }inline void err(bool b = true) {if(b) {cout << -1 << '\n';exit(0);}}template <class T>inline void fin(bool b = true, T e = 0) {if(b) {cout << e << '\n';exit(0);}}template <class T>T divup(T x, T y) { return (x + (y - 1)) / y; }template <typename T>T pow(T a, long long n, T e = 1) {T ret = e;while(n) {if(n & 1) ret *= a;a *= a;n >>= 1;}return ret;}struct iofast {iofast() {ios::sync_with_stdio(false);cin.tie(nullptr);cout << fixed << setprecision(15);}} iofast_;const int inf = 1e9;const ll INF = 1e18;#pragma endregionstruct Edge {int to;long long cost;Edge() = default;Edge(int to_, long long cost_): to(to_), cost(cost_) {}bool operator<(const Edge &a) const {return cost < a.cost;}bool operator>(const Edge &a) const {return cost > a.cost;}friend std::ostream &operator<<(std::ostream &s, Edge &a) {s << "to:" << a.to << " cost:" << a.cost;return s;}};struct Graph : private std::vector<std::vector<Edge>> {using std::vector<std::vector<Edge>>::vector;using std::vector<std::vector<Edge>>::operator[];using std::vector<std::vector<Edge>>::operator=;using std::vector<std::vector<Edge>>::size;using std::vector<std::vector<Edge>>::resize;using std::vector<std::vector<Edge>>::clear;using std::vector<std::vector<Edge>>::push_back;using std::vector<std::vector<Edge>>::emplace_back;using std::vector<std::vector<Edge>>::begin;using std::vector<std::vector<Edge>>::end;private:const long long INF = 1e18;bool isweight = true, lcainit_done = false;std::vector<std::vector<int>> parent;std::vector<int> lcadist;template <class T>inline bool chmax(T &a, T b) {if(a < b) {a = b;return true;}return false;}template <class T>inline bool chmin(T &a, T b) {if(a > b) {a = b;return true;}return false;}vector<pii> edges;public:void read(int e = -1, bool weight = 0, bool directed = false, int idx = 1) {if(e == -1) e = size() - 1;if(!weight) isweight = false;while(e--) {int u, v;long long cost = 1;std::cin >> u >> v;if(weight) std::cin >> cost;u -= idx, v -= idx;edges.eb(u, v);(*this)[u].emplace_back(v, cost);if(!directed) (*this)[v].emplace_back(u, cost);}}void add(int u, int v, int cost = -1, bool directed = false, int idx = 1) {if(cost != -1)isweight = true;elsecost = 1;u -= idx, v -= idx;(*this)[u].emplace_back(v, cost);if(!directed) (*this)[v].emplace_back(u, cost);}std::vector<long long> Dijkstra(int s) {std::vector dist(size(), INF);if(isweight) {using pll = std::pair<long long, long long>;std::priority_queue<pll, std::vector<pll>, std::greater<pll>> que;dist[s] = 0;que.push(pll(0, s));while(!que.empty()) {pll p = que.top();que.pop();int v = p.second;if(dist[v] < p.first) continue;for(int i = 0; i < int((*this)[v].size()); i++) {Edge e = (*this)[v][i];if(dist[e.to] > dist[v] + e.cost) {dist[e.to] = dist[v] + e.cost;que.push(pll(dist[e.to], e.to));}}}return dist;} else {std::vector dist(size(), INF);std::queue<int> que;dist[s] = 0;que.push(s);while(!que.empty()) {int v = que.front();que.pop();for(auto nv : (*this)[v]) {if(dist[nv.to] != INF) continue;dist[nv.to] = dist[v] + 1;que.push(nv.to);}}return dist;}}std::vector<long long> BellmanFord(int s) {int n = size();std::vector res(n, INF);res[s] = 0;for(int loop = 0; loop < n - 1; loop++) {for(int v = 0; v < n; v++) {if(res[v] == INF) continue;for(auto &e : (*this)[v]) {res[e.to] = std::min(res[e.to], res[v] + e.cost);}}}std::queue<int> que;std::vector chk(n, 0);for(int v = 0; v < n; v++) {if(res[v] == INF) continue;for(auto &e : (*this)[v]) {if(res[e.to] > res[v] + e.cost) {res[e.to] = res[v] + e.cost;if(!chk[e.to]) {que.push(e.to);chk[e.to] = 1;}}}}while(!que.empty()) {int now = que.front();que.pop();for(auto &e : (*this)[now]) {if(!chk[e.to]) {chk[e.to] = 1;que.push(e.to);}}}for(int i = 0; i < n; i++)if(chk[i]) res[i] = -INF;return res;}std::vector<std::vector<long long>> WarshallFloyd() {int n = size();std::vector dist(n, std::vector(n, INF));for(int i = 0; i < n; i++) {dist[i][i] = 0;}for(int i = 0; i < n; i++) {for(auto e : (*this)[i]) {chmin(dist[i][e.to], e.cost);}}for(int k = 0; k < n; k++)for(int i = 0; i < n; i++)for(int j = 0; j < n; j++)chmin(dist[i][j], dist[i][k] + dist[k][j]);return dist;}int lca(int u, int v) {std::function<void(int, int, int)> dfs = [&](int now, int per, int d) {parent[0][now] = per;lcadist[now] = d;for(auto &e : (*this)[now])if(e.to != per) dfs(e.to, now, d + 1);};if(!lcainit_done) {lcainit_done = true;int n = size();int k = 1;while((1 << k) < n) k++;parent.assign(k, std::vector(n, -1));lcadist.assign(n, -1);dfs(0, -1, 0);for(int i = 0; i < k - 1; i++)for(int v = 0; v < n; v++) {if(parent[i][v] < 0)parent[i + 1][v] = -1;elseparent[i + 1][v] = parent[i][parent[i][v]];}}if(lcadist[u] < lcadist[v]) std::swap(u, v);int k = parent.size();for(int i = 0; i < k; i++)if((lcadist[u] - lcadist[v]) >> i & 1) u = parent[i][u];if(u == v) return u;for(int i = k - 1; i >= 0; i--)if(parent[i][u] != parent[i][v])u = parent[i][u], v = parent[i][v];return parent[0][u];}int dist(int u, int v) { return lcadist[u] + lcadist[v] - 2 * lcadist[lca(u, v)]; }std::vector<int> tsort() {std::vector<int> res;int n = size();std::vector<int> used(n, 0);bool notDAG = false;std::function<void(int)> dfs = [&](int k) {if(notDAG) return;if(used[k]) {if(used[k] == 1)notDAG = true;return;}used[k] = 1;for(auto &e : (*this)[k]) dfs(e.to);used[k] = 2;res.push_back(k);};for(int i = 0; i < n; i++) dfs(i);if(notDAG) return std::vector<int>{};std::reverse(res.begin(), res.end());return res;}bool isDAG() { return tsort().size(); }std::vector<long long> height() {std::vector<long long> fir(size(), -1), sec(size(), -1);std::function<long long(int, int)> dfs = [&](int now, int par) {long long f = 0, s = 0;for(auto &e : (*this)[now]) {if(e.to == par) continue;s = std::max(s, dfs(e.to, now) + e.cost);if(f < s) std::swap(f, s);}sec[now] = s;return fir[now] = f;};std::function<void(int, int, long long, long long, long long)> solve = [&](int now, int par, long long parf, long long pars, long longparcost) {if(fir[now] + parcost == parf) parf = pars;sec[now] = std::max(sec[now], parf + parcost);if(fir[now] < sec[now]) std::swap(fir[now], sec[now]);for(auto &e : (*this)[now]) {if(e.to == par) continue;solve(e.to, now, fir[now], sec[now], e.cost);}return;};dfs(0, -1);solve(0, -1, -1, -1, -1);return fir;}//{二部グラフか、二部グラフのどちらに属するかを0か1で表した配列}std::pair<bool, std::vector<int>> isBiparate() {std::vector<int> colors(size()), ret(size());std::function<bool(int, int)> dfs = [&](int now, int col) {colors[now] = col;if(col == 1) ret[now] = 1;for(auto &e : (*this)[now]) {if(col == colors[e.to]) return false;if(colors[e.to] == 0 and !dfs(e.to, -col)) return false;}return true;};return std::pair(dfs(0, 1), ret);}//{{端点、端点},直径の大きさ}std::pair<std::pair<int, int>, long long> Diameter() {auto vec = Dijkstra(0);int v1 = -1, v2 = -1;long long dia = -1;for(int i = 0; i < int(size()); i++)if(chmax(dia, vec[i]))v1 = i;vec = Dijkstra(v1);dia = -1;for(int i = 0; i < int(size()); i++)if(chmax(dia, vec[i]))v2 = i;std::pair<std::pair<int, int>, long long> res = {{v1, v2}, dia};return res;}//最小全域木long long Prim() {long long res = 0;std::priority_queue<Edge, std::vector<Edge>, std::greater<Edge>> que;for(auto &e : (*this)[0])que.push(e);std::vector chk(size(), 0);chk[0] = 1;while(!que.empty()) {auto e = que.top();que.pop();if(chk[e.to]) continue;res += e.cost;chk[e.to] = 1;for(auto &e : (*this)[e.to]) {que.push(e);}}return res;}//重心std::vector<int> Centroid() {int n = size();std::vector<int> centroid, sz(n);std::function<void(int, int)> dfs = [&](int now, int per) {sz[now] = 1;bool is_centroid = true;for(auto &e : (*this)[now])if(e.to != per) {dfs(e.to, now);sz[now] += sz[e.to];if(sz[e.to] > n / 2) is_centroid = false;}if(n - sz[now] > n / 2) is_centroid = false;if(is_centroid) centroid.push_back(now);};return centroid;}//pair{橋(pairの配列),関節点(intの配列)}std::pair<std::vector<std::pair<int, int>>, std::vector<int>> lowlink() {int n = size(), k = 0;std::vector<int> used(n, 0), order(n, 0), low(n, 0), articulation;std::vector<std::pair<int, int>> bridge;std::function<int(int, int, int)> dfs = [&](int idx, int k, int par) {used[idx] = 1;order[idx] = k++;low[idx] = order[idx];bool is_articulation = false, neko = false;int cnt = 0;for(auto &e : (*this)[idx]) {if(e.to == par and !std::exchange(neko, true)) {continue;}if(!used[e.to]) {++cnt;k = dfs(e.to, k, idx);low[idx] = std::min(low[idx], low[e.to]);is_articulation |= par >= 0 and low[e.to] >= order[idx];if(order[idx] < low[e.to]) {auto p = std::minmax(idx, e.to);bridge.emplace_back(p.first, p.second);}} else {low[idx] = std::min(low[idx], order[e.to]);}}is_articulation |= par == -1 and cnt > 1;if(is_articulation) articulation.push_back(idx);return k;};for(int i = 0; i < n; i++)if(!used[i]) k = dfs(i, k, -1);return std::pair(bridge, articulation);}//根から葉への有向グラフGraph RootToLeaf(int root = 0) {Graph res(size());std::vector chk(size(), 0);chk[root] = 1;std::function<void(int)> dfs = [&](int now) {for(auto &e : (*this)[now]) {if(chk[e.to] == 1) continue;chk[e.to] = 1;res.add(now, e.to, e.cost, 1, 0);dfs(e.to);}};dfs(root);return res;}//葉から根への有向グラフGraph LeafToRoot(int root = 0) {Graph res(size());std::vector chk(size(), 0);chk[root] = 1;std::function<void(int)> dfs = [&](int now) {for(auto &e : (*this)[now]) {if(chk[e.to] == 1) continue;chk[e.to] = 1;res.add(e.to, now, e.cost, 1, 0);dfs(e.to);}};dfs(root);return res;}//辺(from,to)を返す(無向ならu->vとv->u共に入る)std::vector<std::pair<int, int>> getedges() {return edges;}//辺(from,to,cost)を返す(無向ならu->vとv->u共に入る)std::vector<std::tuple<int, int, long long>> getwedges() {std::vector<std::tuple<int, int, long long>> ret;for(int i = 0; i < size(); i++) {for(auto &e : (*this)[i]) ret.emplace_back(i, e.to, e.cost);}return ret;}};//Strongly Connected Components(強成分連結分解)(Graph Templateと併用)struct SCC {const Graph &g;Graph ng, rg;V<int> compo, order, used;//g:元のグラフ, ret:強連結成分分解後のグラフSCC(Graph &g, Graph &ret) : g(g), ng(SZ(g)), rg(SZ(g)), compo(SZ(g), -1), used(SZ(g)) {REP(i, SZ(g)) {for(auto &v : g[i]) {ng[i].eb(v.to, 1);rg[v.to].eb(i, 1);}}build(ret);}int operator[](int k) { return compo[k]; }void dfs(int now) {if(used[now]) return;used[now] = true;for(auto &e : ng[now]) dfs(e.to);order.eb(now);}void rdfs(int now, int count) {if(compo[now] != -1) return;compo[now] = count;for(auto &e : rg[now]) rdfs(e.to, count);}void build(Graph &ret) {REP(i, SZ(ng))dfs(i);reverse(all(order));int group = 0;for(auto i : order)if(compo[i] == -1) rdfs(i, group), group++;ret.resize(group);REP(i, SZ(g)) {for(auto &e : g[i]) {int s = compo[i], t = compo[e.to];if(s != t) ret[s].eb(t, 1);}}}};int main() {INT(n, m);vector res(m, 0);Graph G(n);G.read(m, 0, 1);Graph ret;SCC scc(G, ret);if(ret.size() > 1) dump(-1);if(G.isBiparate().first) dump(-1);V<> ver;int shortest = n + 1;REP(i, n) {vector dist(n, -1);vector prev(n, -1);queue<int> que;que.push(i);dist[i] = 0;while(SZ(que)) {int now = que.front();que.pop();for(auto &e : G[now]) {int to = e.to;if(dist[to] == -1) {dist[to] = dist[now] + 1;prev[to] = now;que.push(to);}}}REP(j, n) {if(j == i or dist[j] == -1) continue;for(auto &e : G[j]) {if(e.to == i) {vector tmp(1, i);int cur = j;while(cur != i) tmp.pb(cur), cur = prev[cur];if(shortest > SZ(tmp)) {shortest = SZ(tmp);ver = tmp;}}}}}reverse(all(ver));if(SZ(ver) == m) dump(-1);ver.pb(ver[0]);auto E = G.getedges();map<pii, int> encode;REP(i, SZ(E)) { encode[E[i]] = i; }debug(ver);int tmp = (SZ(ver) - 1) / 2 + 1;debug(tmp);V<pii> chk;REP(i, SZ(ver) - 1) {chk.eb(encode[{ver[i], ver[i + 1]}], SZ(G[ver[i]]));}sort(all(chk), [](pii a, pii b) { return a.second > b.second; });REP(i, tmp) { res[chk[i].first] = 1; }string ans = "";REP(i, m) { ans += (res[i] ? 'G' : 'R'); }dump(ans);}