{"blog_url":"https://junkobayashi.hatenablog.com/","author_name":"JunKobayashi","provider_name":"Hatena Blog","image_url":null,"version":"1.0","provider_url":"https://hatena.blog","width":"100%","url":"https://junkobayashi.hatenablog.com/entry/2026/08/19/002930","blog_title":"JunKobayashi's Diary","published":"2026-08-19 00:29:30","title":"ABC471 E - Sum of Square of Sum","height":"190","categories":["ABC\u306eE\u554f\u984c","\u4e8c\u91cd\u30b7\u30b0\u30de","\u4e8c\u9805\u4fc2\u6570mod"],"description":"ABC471 E - Sum of Square of Sum \u4e0d\u53c2\u52a0\u306e\u56de\u3067\u51fa\u984c\u3055\u308c\u305f\u4e0a\u8a18\u306e\u554f\u984c\u3092\u901a\u3057\u3066\u4e8c\u91cd\u30b7\u30b0\u30de\u554f\u984c\u3078\u306e\u624b\u672d\u3092\u5897\u3084\u3059\u3053\u3068\u3092\u76ee\u7684\u3068\u3057\u3066\u66f8\u304f\u3002\u306a\u304a\u3001\\(P = 998244353\\)\u3068\u3059\u308b\u3002 \uff1c\u554f\u984c\u6982\u8981\uff1e 2\u3064\u306e\u6574\u6570\u5024\\(N,K\\)\u3068\\(N\\)\u500b\u306e\u6574\u6570\u5024\\(A_1, A_2, \\dots , A_N\\)\u304c\u4e0e\u3048\u3089\u308c\u308b\u3002\\(N\\)\u500b\u306e\u6574\u6570\u5024\u304b\u3089\\(K\\)\u500b\u3092\u9078\u3073\u51fa\u3059\u7d44\u5408\u305b\u306f\u5168\u90e8\u3067\\( \\binom{N}{K} \\)\u901a\u308a\u3060\u3051\u5b58\u5728\u3059\u308b\u304c\u3001\u305d\u308c\u3089\u5168\u3066\u306b\u5bfe\u3057\u3066\u300c\u9078\u3073\u51fa\u3055\u308c\u305f\\(K\\)\u500b\u306e\u6574\u6570\u5024\u306e\u7dcf\u548c\u30922\u4e57\u3057\u305f\u5024\u300d\u3092\u8a08\u7b97\u3057\u305f\u7d50\u679c\u306e\u7dcf\u548c\u3092\\( \\mod P\\)\u306e\u3082\u3068\u3067\u6c42\u3081\u3088\u3002 \uff1c\u5236\u7d04\uff1e \\(1 \u2026","author_url":"https://blog.hatena.ne.jp/JunKobayashi/","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fjunkobayashi.hatenablog.com%2Fentry%2F2026%2F08%2F19%2F002930\" title=\"ABC471 E - Sum of Square of Sum - JunKobayashi&#39;s Diary\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","type":"rich"}