在洛谷题目中书写公式，latex 代码如下：

\left\{ \begin{array}[lr] \newline a_{1, 1} x_1 + a_{1, 2} x_2 + \cdots + a_{1, n - 1} x_{n - 1} + a_{1, n} x_n = b_1 \newline a_{2, 1} x_1 + a_{2, 2} x_2 + \cdots + a_{2, n - 1} x_{n - 1} + a_{2, n} x_n = b_2 \newline \cdots \newline a_{n - 1, 1} x_1 + a_{n - 1, 2} x_2 + \cdots + a_{n - 1, n - 1} x_{n - 1} + a_{n - 1, n} x_n = b_{n - 1} \newline a_{n, 1} x_1 + a_{n, 2} x_2 + \cdots + a_{n, n - 1} x_{n - 1} + a_{n, n} x_n = b_n \newline \end{array} \right. 

但无法正常渲染