結果

問題 No.1103 Directed Length Sum
コンテスト
ユーザー mikianaaa
提出日時 2020-08-20 15:43:38
言語 C++14
(gcc 13.3.0 + boost 1.87.0)
結果
WA  
実行時間 -
コード長 1,733 bytes
コンパイル時間 1,729 ms
コンパイル使用メモリ 177,152 KB
実行使用メモリ 69,632 KB
最終ジャッジ日時 2024-10-13 11:44:01
合計ジャッジ時間 9,729 ms
ジャッジサーバーID
（参考情報） 		judge4 / judge5
このコードへのチャレンジ
（要ログイン）
ファイルパターン 結果
sample AC * 2
other AC * 21 WA * 1
権限があれば一括ダウンロードができます
コンパイルメッセージ
In file included from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/x86_64-pc-linux-gnu/bits/c++allocator.h:33,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/bits/allocator.h:46,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/string:41,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/bits/locale_classes.h:40,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/bits/ios_base.h:41,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/ios:42,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/istream:38,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/sstream:38,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/complex:45,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/ccomplex:39,
                 from /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/x86_64-pc-linux-gnu/bits/stdc++.h:54,
                 from main.cpp:2:
In member function 'void std::__new_allocator<_Tp>::construct(_Up*, _Args&& ...) [with _Up = int; _Args = {const int&}; _Tp = int]',
    inlined from 'static void std::allocator_traits<std::allocator<_CharT> >::construct(allocator_type&, _Up*, _Args&& ...) [with _Up = int; _Args = {const int&}; _Tp = int]' at /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/bits/alloc_traits.h:516:17,
    inlined from 'void std::deque<_Tp, _Alloc>::push_back(const value_type&) [with _Tp = int; _Alloc = std::allocator<int>]' at /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/include/c++/12/bits/stl_deque.h:1543:30,
    inlined from 'void std::queue<_Tp, _Sequence>::push(const value_type&) [with _Tp = int; _Sequence = std::deque<int, std::allocator<int> >]' at /home/linuxbrew/.linuxbrew/Cellar/gcc@12/12.3.0/

ソースコード

diff # 

#include <algorithm>
#include <bits/stdc++.h>
using namespace std;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define all(x) (x).begin(), (x).end()
#define ll long long
#define ld long double
#define INF 1000000000000000000
typedef pair<ll, ll> pll;

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);

    int N;
    cin >> N;
    ll MOD = pow(10, 9) + 7;
    vector<vector<int>> G(N, vector<int>());
    vector<int> root(N, -1);
    rep(i, N - 1) {
        int a, b;
        cin >> a >> b;
        a--, b--;
        G[a].push_back(b);
        root[b] = a;
    }

    int s;
    rep(i, N) {
        if (root[i] == -1) {
            s = i;
            break;
        }
    }

    vector<ll> dist(N, -1); // 全頂点を「未訪問」に初期化
    queue<int> que;

    // 初期条件 (頂点 0 を初期ノードとする)
    dist[s] = 0;
    que.push(s); // 0 を橙色頂点にする

    // BFS 開始 (キューが空になるまで探索を行う)
    while (!que.empty()) {
        int v = que.front(); // キューから先頭頂点を取り出す
        que.pop();

        // v から辿れる頂点をすべて調べる
        for (int nv : G[v]) {
            if (dist[nv] != -1)
                continue; // すでに発見済みの頂点は探索しない

            // 新たな白色頂点 nv について距離情報を更新してキューに追加する
            dist[nv] = dist[v] + 1;
            dist[nv] %= MOD;
            que.push(nv);
        }
    }

    ll ans = 0;
    rep(i, N) {
        ll tmp = dist[i];
        if (dist[i] >= 2) {
            tmp = (1 + dist[i]) * dist[i] % MOD / 2;
        }

        ans += tmp;
        ans %= MOD;
    }

    cout << ans << endl;
}
0