Description Mr. Young wishes to take a picture of his class. The students will stand in rows with each row no longer than the row behind it and the left ends of the rows aligned. For instance, 12 students could be arranged in rows (from back to front
在进行latex引用时,有两种办法: 一,被动引用. 如有这样一段代码: $$ x^2+y^2= z^2.\eqno(1.1) $$ In this paper, we investigated (1.1) and applied it into some fields. 红色部分为被动引用,其缺点显而易见:如果公式(1.1)的编号修改之后,引用出的编号也得跟着修改才行,麻烦且易出错. 因此推荐下一种引用方式. 二,自动引用. 如有这样一段代码: \begin{ea}\label{equ:squ