結果
問題 |
No.1424 Ultrapalindrome
|
ユーザー |
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提出日時 | 2023-06-19 18:27:15 |
言語 | C++17 (gcc 13.3.0 + boost 1.87.0) |
結果 |
AC
|
実行時間 | 92 ms / 2,000 ms |
コード長 | 1,448 bytes |
コンパイル時間 | 2,122 ms |
コンパイル使用メモリ | 202,464 KB |
最終ジャッジ日時 | 2025-02-14 23:00:16 |
ジャッジサーバーID (参考情報) |
judge1 / judge1 |
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ファイルパターン | 結果 |
---|---|
sample | AC * 3 |
other | AC * 29 |
コンパイルメッセージ
main.cpp: In function ‘int main()’: main.cpp:74:37: warning: ‘d’ may be used uninitialized [-Wmaybe-uninitialized] 74 | cout << (cnt == d ? "Yes" : "No") << endl; | ^ main.cpp:31:33: note: ‘d’ was declared here 31 | int N, a, b, cnt=0, cnt2=0, d, e; | ^ main.cpp:61:32: warning: ‘e’ may be used uninitialized [-Wmaybe-uninitialized] 61 | vector<int> dist = bfs(E, e); | ^ main.cpp:31:36: note: ‘e’ was declared here 31 | int N, a, b, cnt=0, cnt2=0, d, e; | ^
ソースコード
#include <bits/stdc++.h> using namespace std; using ll = long long; vector<int> bfs(vector<vector<int>> &E, int start){ int N = E.size(); int from, to; queue<int> que; vector<int> dist(N, 1e9); dist[start] = 0; que.push(start); while(!que.empty()){ from = que.front(); que.pop(); for (auto to : E[from]){ if (dist[to] != 1e9) continue; dist[to] = dist[from] + 1; que.push(to); } } return dist; } int main(){ int N, a, b, cnt=0, cnt2=0, d, e; cin >> N; vector<int> deg(N); vector<vector<int>> E(N); for (int i=0; i<N-1; i++){ cin >> a >> b; a--; b--; deg[a]++; deg[b]++; E[a].push_back(b); E[b].push_back(a); } for (int i=0; i<N; i++){ if (deg[i] == 1) cnt++; else if (deg[i] >= 3){ cnt2++; d = deg[i]; e = i; } } if (cnt == 2){ cout << "Yes" << endl; return 0; } else if (cnt2 > 1){ cout << "No" << endl; return 0; } vector<int> dist = bfs(E, e); vector<int> v; for (int i=0; i<N; i++){ if (deg[i] == 1) v.push_back(dist[i]); } for (int i=0; i<v.size(); i++){ if (v[i] != v[0]){ cout << "No" << endl; return 0; } } cout << (cnt == d ? "Yes" : "No") << endl; return 0; }