{"width":"100%","url":"https://kaage.hatenablog.com/entry/2021/03/01/020050","image_url":"https://cdn.user.blog.st-hatena.com/default_entry_og_image/154818125/1592546778599961","description":"\u554f\u984c\u30ea\u30f3\u30af \u6570\u3048\u4e0a\u3052\uff0c\u82e6\u624b \u89e3\u8aac \u6570\u3092\u30b0\u30eb\u30fc\u30d7\u306b\u3057\u3066\u8003\u3048\u308b\uff0e$h$ \u306b\u542b\u307e\u308c\u308b $i$ \u306e\u6570\u3092 $n_i$ \u3068\u3057\u3066\u304a\u304f\uff0e $n_i$ \u500b\u306e\u6570\u304c\u3042\u308b\u30b0\u30eb\u30fc\u30d7\u306e\u4e2d\u306b\u91cd\u8907\u3092\u5c11\u306a\u304f\u3068\u3082 $k$ \u30da\u30a2\u4f5c\u308b\u65b9\u6cd5\u306e\u6570\u306f $\\binom{n_i}{2k}(2k-1)!!$ \u901a\u308a\u3042\u308b\uff0e \u3053\u308c\u3092\u591a\u9805\u5f0f\u306e\u4fc2\u6570\u306b\u3057\u3066\u7573\u307f\u8fbc\u307f\u3059\u308b\u3068\uff0c\u5168\u4f53\u306b\u3064\u3044\u3066\u91cd\u8907\u3092\u5c11\u306a\u304f\u3068\u3082 $k$ \u30da\u30a2\u4f5c\u308b\u65b9\u6cd5\u306e\u6570\u304c\u6c42\u307e\u308b\uff0e \u3053\u308c\u304c\u6c42\u307e\u3063\u305f\u3089\uff0c\u6b8b\u308a\u306e\u7d44\u307f\u65b9\u306f $(2N-2K-1)!!$ \u901a\u308a\u3042\u308b\u306e\u3067\uff0c\u3053\u308c\u3092\u304b\u3051\u3066\u5305\u9664\u3059\u308b\u3068\u89e3\u3051\u308b\uff0e \u7573\u307f\u8fbc\u307f\u306f\uff0cFFT\u3092\u5e73\u8861\u4e8c\u5206\u6728\u3092\u4f5c\u308b\u8981\u9818\u3067\u3084\u308b\u3068 $O(N\\log^2N)$ \u306a\u306e\u3067\uff0c\u5168\u4f53\u3067\u3082 $O(N\\log^2\u2026","author_url":"https://blog.hatena.ne.jp/kaage/","provider_name":"Hatena Blog","height":"190","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fkaage.hatenablog.com%2Fentry%2F2021%2F03%2F01%2F020050\" title=\"ACL Beginner Contest F - Height and Pairs \u89e3\u8aac - kaage\u7cbe\u9032\u9332\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","title":"ACL Beginner Contest F - Height and Pairs \u89e3\u8aac","author_name":"kaage","provider_url":"https://hatena.blog","blog_title":"kaage\u7cbe\u9032\u9332","version":"1.0","categories":[],"type":"rich","blog_url":"https://kaage.hatenablog.com/","published":"2021-03-01 02:00:50"}