{"problem":{"name":"BZOJ4174 tty 的求助","description":{"content":"计算下式对 $998244353$ 取模的值，其中 $x$ 为实数，其余参与运算的变量均为整数： $$\\sum_{n=1}^N \\sum_{m=1}^M \\sum_{k=0}^{m-1} \\lfloor \\dfrac{nk+x}{m}\\rfloor$$","description_type":"Markdown"},"platform":"Luogu","limit":{"time_limit":1000,"memory_limit":524288},"difficulty":{"LuoguStyle":"P6"},"is_remote":true,"is_sync":true,"sync_url":null,"sign":"LGP10670"},"statements":[{"statement_type":"Markdown","content":"计算下式对 $998244353$ 取模的值，其中 $x$ 为实数，其余参与运算的变量均为整数：\n\n$$\\sum_{n=1}^N \\sum_{m=1}^M \\sum_{k=0}^{m-1} \\lfloor \\dfrac{nk+x}{m}\\rfloor$$\n\n## Input\n\n输入一行，两个正整数 $N,M$ 和一个实数 $x$。\n\n## Output\n\n输出一行一个整数，表示答案对 $998244353$ 取模的值。\n\n[samples]\n\n## Note\n\n数据保证，$1\\leq N,M\\leq 500000$，$0<x\\leq 100000$，$x$ 精确到小数点后 $8$ 位小数。","is_translate":false,"language":"English"}],"meta":{"iden":"LGP10670","tags":["O2优化","莫比乌斯反演"],"sample_group":[["2 3 1 ","7"]],"created_at":"2026-03-03 11:09:25"}}