latex版本-伪代码排版

\documentclass[11pt]{ctexart}  
\usepackage[top=2cm, bottom=2cm, left=2cm, right=2cm]{geometry}  
\usepackage{algorithm}  
\usepackage{algorithmicx}  
\usepackage{algpseudocode}  
\usepackage{amsmath}  

\floatname{algorithm}{算法}  
\renewcommand{\algorithmicrequire}{\textbf{输入:}}  
\renewcommand{\algorithmicensure}{\textbf{输出:}}  

\begin{document}  
	\begin{algorithm}  
		\caption{用归并排序求逆序数}  
		\begin{algorithmic}[1] %每行显示行号  
			\Require $Array$数组，$n$数组大小  
			\Ensure 逆序数  
			\Function {MergerSort}{$Array, left, right$}  
			\State $result \gets 0$  
			\If {$left < right$}  
			\State $middle \gets (left + right) / 2$  
			\State $result \gets result +$ \Call{MergerSort}{$Array, left, middle$}  
			\State $result \gets result +$ \Call{MergerSort}{$Array, middle, right$}  
			\State $result \gets result +$ \Call{Merger}{$Array,left,middle,right$}  
			\EndIf  
			\State \Return{$result$}  
			\EndFunction  
			\State  
			\Function{Merger}{$Array, left, middle, right$}  
			\State $i\gets left$  
			\State $j\gets middle$  
			\State $k\gets 0$  
			\State $result \gets 0$  
			\While{$i<middle$ \textbf{and} $j<right$}  
			\If{$Array[i]<Array[j]$}  
			\State $B[k++]\gets Array[i++]$  
			\Else  
			\State $B[k++] \gets Array[j++]$  
			\State $result \gets result + (middle - i)$  
			\EndIf  
			\EndWhile  
			\While{$i<middle$}  
			\State $B[k++] \gets Array[i++]$  
			\EndWhile  
			\While{$j<right$}  
			\State $B[k++] \gets Array[j++]$  
			\EndWhile  
			\For{$i = 0 \to k-1$}  
			\State $Array[left + i] \gets B[i]$  
			\EndFor  
			\State \Return{$result$}  
			\EndFunction  
		\end{algorithmic}  
	\end{algorithm}  
\end{document}