deletions | additions       diff --git a/untitled.tex b/untitled.tex  index e56f64d..c0c8e9f 100644  --- a/untitled.tex  +++ b/untitled.tex 
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\documentclass[12pt]{article}{\twocolumn} \documentclass[12pt,twocolumn]{article}  \usepackage{hyperref}  \usepackage{amsmath}