deletions | additions       diff --git a/untitled.tex b/untitled.tex  index 25b2f61..e56f64d 100644  --- a/untitled.tex  +++ b/untitled.tex 
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\documentclass[12pt]{article}{twocolumn} \documentclass[12pt]{article}{\twocolumn}  \usepackage{hyperref}  \usepackage{amsmath}