結果
| 問題 | 
                            No.1023 Cyclic Tour
                             | 
                    
| コンテスト | |
| ユーザー | 
                             kcvlex
                         | 
                    
| 提出日時 | 2020-04-10 22:33:41 | 
| 言語 | C++14  (gcc 13.3.0 + boost 1.87.0)  | 
                    
| 結果 | 
                             
                                WA
                                 
                             
                            
                         | 
                    
| 実行時間 | - | 
| コード長 | 7,811 bytes | 
| コンパイル時間 | 1,902 ms | 
| コンパイル使用メモリ | 155,636 KB | 
| 実行使用メモリ | 47,916 KB | 
| 最終ジャッジ日時 | 2024-09-15 21:04:11 | 
| 合計ジャッジ時間 | 20,344 ms | 
| 
                            ジャッジサーバーID (参考情報)  | 
                        judge1 / judge2 | 
(要ログイン)
| ファイルパターン | 結果 | 
|---|---|
| sample | AC * 4 | 
| other | AC * 34 WA * 15 | 
ソースコード
#include <limits>
#include <initializer_list>
#include <utility>
#include <bitset>
#include <tuple>
#include <type_traits>
#include <functional>
#include <string>
#include <array>
#include <deque>
#include <list>
#include <queue>
#include <stack>
#include <vector>
#include <map>
#include <set>
#include <unordered_map>
#include <unordered_set>
#include <iterator>
#include <algorithm>
#include <complex>
#include <random>
#include <numeric>
#include <iostream>
#include <iomanip>
#include <sstream>
#include <regex>
#include <cassert>
#include <cstddef>
#define endl codeforces
#define ALL(v) std::begin(v), std::end(v)
#define ALLR(v) std::rbegin(v), std::rend(v)
using ll = std::int64_t;
using ull = std::uint64_t;
using pii = std::pair<int, int>;
using tii = std::tuple<int, int, int>;
using pll = std::pair<ll, ll>;
using tll = std::tuple<ll, ll, ll>;
template <typename T> using vec = std::vector<T>;
template <typename T> using vvec = vec<vec<T>>;
template <typename T> const T& var_min(const T &t) { return t; }
template <typename T> const T& var_max(const T &t) { return t; }
template <typename T, typename... Tail> const T& var_min(const T &t, const Tail&... tail) { return std::min(t, var_min(tail...)); }
template <typename T, typename... Tail> const T& var_max(const T &t, const Tail&... tail) { return std::max(t, var_max(tail...)); }
template <typename T, typename... Tail> void chmin(T &t, const Tail&... tail) { t = var_min(t, tail...); }
template <typename T, typename... Tail> void chmax(T &t, const Tail&... tail) { t = var_max(t, tail...); }
template <typename T> const T& clamp(const T &t, const T &low, const T &high) { return std::max(low, std::min(high, t)); }
template <typename T> void chclamp(T &t, const T &low, const T &high) { return t = clamp(t, low, high); }
template <typename T> T make_v(T init) { return init; }
template <typename T, typename... Tail> auto make_v(T init, std::size_t s, Tail... tail) { auto v = std::move(make_v(init, tail...)); return vec<decltype(v)>(s, v); }
template <typename T, std::size_t Head, std::size_t ...Tail> struct multi_dem_array { using type = std::array<typename multi_dem_array<T, Tail...>::type, Head>; };
template <typename T, std::size_t Head> struct multi_dem_array<T, Head> { using type = std::array<T, Head>; };
template <typename T, std::size_t ...Args> using mdarray = typename multi_dem_array<T, Args...>::type;
namespace init__ { struct InitIO { InitIO() { std::cin.tie(nullptr); std::ios_base::sync_with_stdio(false); std::cout << std::fixed << std::setprecision(30); } } init_io; }
namespace graph {
using Node = ll;
using Weight = ll;
using Edge = std::pair<Node, Weight>;
template <bool Directed>
struct Graph : public vvec<Edge> {
    using vvec<Edge>::vvec;
    void add_edge(Node f, Node t, Weight w = 1) {
        (*this)[f].emplace_back(t, w);
        if (!Directed) (*this)[t].emplace_back(f, w);
    }
    Graph<Directed> build_inv() const {
        Graph<Directed> ret(this->size());
        for (Node i = 0; i < this->size(); i++) {
            for (const Edge &e : (*this)[i]) {
                Node j;
                Weight w;
                std::tie(j, w) = e;
                if (!Directed && j < i) continue;
                ret.add_edge(j, i, w);
            }
        }
        return ret;
    }
};
template <typename Iterator>
class dst_iterator {
    Iterator ite;
public:
    dst_iterator(Iterator ite) : ite(ite) { }
    bool operator ==(const dst_iterator<Iterator> &oth) const {
        return ite == oth.ite;
    }
    bool operator !=(const dst_iterator<Iterator> &oth) const {
        return !(*this == oth);
    }
    bool operator <(const dst_iterator<Iterator> &oth) const {
        return ite < oth.ite;
    }
    bool operator >(const dst_iterator<Iterator> &oth) const {
        return ite > oth.ite;
    }
    bool operator <=(const dst_iterator<Iterator> &oth) const {
        return ite <= oth.ite;
    }
    bool operator >=(const dst_iterator<Iterator> &oth) const {
        return ite >= oth.ite;
    }
    const Node& operator *() {
        return ite->first;
    }
    const Node& operator *() const {
        return ite->first;
    }
    dst_iterator operator ++() {
        ++ite;
        return ite;
    }
};
class dst_iteration {
    using ite_type = vec<Edge>::const_iterator;
    const vec<Edge> &edges;
public:
    dst_iteration(const vec<Edge> &edges) : edges(edges) { }
    auto begin() const {
        return dst_iterator<ite_type>(edges.cbegin());
    }
    auto end() const {
        return dst_iterator<ite_type>(edges.cend());
    }
};
dst_iteration dst(const vec<Edge> &edges) {
    return dst_iteration(edges);
}
}
namespace graph {
template <typename Graph>
class StronglyConnectedComponents {
    const Graph &graph;
    Graph rgraph;
    vec<ll> label, scc_ord;
    void dfs1(ll cur, ll &l) {
        label[cur] = -2;
        for (const graph::Edge &e : graph[cur]) {
            ll nxt;
            std::tie(nxt, std::ignore) = e;
            if (label[nxt] != -1) continue;
            dfs1(nxt, l);
        }
        label[cur] = l++;
    }
    void write_label() {
        ll l = 0;
        for (ll i = 0; i < graph.size(); i++) if (label[i] == -1) dfs1(i, l);
    }
    void dfs2(ll cur, ll l, ll &idx, vec<ll> &result) {
        result[cur] = l;
        scc_ord[idx++] = cur;
        for (const graph::Edge &e : rgraph[cur]) {
            ll nxt;
            std::tie(nxt, std::ignore) = e;
            if (result[nxt] != -1) continue;
            dfs2(nxt, l, idx, result);
        }
    }
    vec<ll> build_scc() {
        ll l = 0;
        vec<ll> result(graph.size(), -1), ord(rgraph.size());
        std::iota(ALL(ord), 0ll);
        std::sort(ALL(ord), [&](ll i, ll j) { return label[i] > label[j]; });
        ll idx = 0;
        for (ll n : ord) if (result[n] == -1) dfs2(n, l++, idx, result);
        return result;
    }
public:
    StronglyConnectedComponents(const Graph &graph)
        : graph(graph), label(graph.size(), -1), scc_ord(graph.size())
    {
        rgraph = graph.build_inv();
    }
    vec<ll> build() {
        vec<ll> result(graph.size(), -1);
        write_label();
        return build_scc();
    }
    std::pair<::graph::Graph<true>, vec<ll>> build_scc_graph() {
        auto scc_label = build();
        ::graph::Graph<true> scc_graph(*max_element(ALL(scc_label)) + 1);
        for (ll from = 0; from < graph.size(); from++) for (auto &&e : graph[from]) {
            ll to;
            std::tie(to, std::ignore) = e;
            ll lf = scc_label[from], lt = scc_label[to];
            if (lf != lt) scc_graph.add_edge(lf, lt);
        }
        return std::make_pair(std::move(scc_graph), std::move(scc_label));
    }
};
template <typename Graph> using SCC = StronglyConnectedComponents<Graph>;
}
bool solve() {
    ll n, m;
    std::cin >> n >> m;
    graph::Graph<true> g(n);
    std::map<pll, vec<ll>> st;
    while (m--) {
        ll a, b, c;
        std::cin >> a >> b >> c;
        a--; b--;
        g.add_edge(a, b);
        if (c == 1) g.add_edge(b, a);
        auto key = pll(std::min(a, b), std::max(a, b));
        if (c == 1) {
            st[key].push_back(2);
        } else {
            st[key].push_back(a > b ? -1 : 1);
        }
    }
    for (auto &&e : st) {
        auto &&v = e.second;
        ll minv = *std::min_element(ALL(v));
        ll maxv = *std::max_element(ALL(v));
        if (2 <= v.size() && maxv == 2) return true;
        if (minv != maxv) return true;
    }
    graph::SCC<graph::Graph<true>> scc(g);
    auto label = scc.build();
    std::map<ll, ll> cnt;
    for (ll e : label) cnt[e]++;
    for (auto &&e : cnt) if (3 <= e.second) return true;
    return false;
}
int main() {
    std::cout << (solve() ? "Yes" : "No") << '\n';
    return 0;
}
            
            
            
        
            
kcvlex