There is my source code.
\documentclass[conference]{IEEEtran}
\usepackage{algorithm}
\usepackage{algorithmic}
%\usepackage{algpseudocode}
\usepackage[algcompatible]{algpseudocode}
\usepackage{amsmath}
\begin{document}
\begin{algorithm}[!b]
\caption{algorithm 1}
\label{alg}
\begin{algorithmic}[1]
\Require
INFORMATION
\Ensure
Model;
\STATE CALCULATE
\STATE END
\RETURN MODEL
\end{algorithmic}
\end{algorithm}
\end{document}
When I compile it, it looks like this. No matter what I modified the content, the zero is always there.

algorithmicandalgpseudocodewhich are not compatible. But I still have no idea how to solve it. – LC Dai Apr 10 '18 at 13:49