an'; mso-hansi-font-family: 'Times New Roman'; mso-bidi-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA">输入文件第一行是用空格隔开的四个正整数</span><span lang="EN-US" style="color: black; font-family: &quot;Times New Roman&quot;; mso-bidi-font-size: 12.0pt; mso-ansi-language: EN-US; mso-fareast-language: ZH-CN; mso-bidi-language: AR-SA; mso-fareast-font-family: 宋体">N</span><span style="color: black; font-family: 宋体;