323. Number of Connected Components in an Undirected Graph #20
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oda
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Jun 27, 2024
| public: | ||
| int countComponents(int n, vector<vector<int>>& edges) { | ||
| vector<vector<int>> adjacency_list(n); | ||
| vector<bool> visited(n, false); |
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false は書かなくても zero initialization だったか自信ありますか。
vector は色々と特殊なので、どこかで調べるといいかもしれません。
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こちら調べてみました。
vectorの場合、false を指定しなくても zero initialization になるんですね。
また、vector<bool> に関しては実装依存ではあるが、各要素がsingle bitに対応付けられるような特殊なメモリ最適化が行われる場合が多いと理解しました。
以下を参考にしました)
https://en.cppreference.com/w/cpp/container/vector
https://en.cppreference.com/w/cpp/container/vector_bool
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問題へのリンク
https://www.lintcode.com/problem/3651/
次に解く問題
127. Word Ladder
README.mdへ頭の中の言語化と記録をしています。