deletions | additions       diff --git a/a) As few classrooms as possible.tex b/a) As few classrooms as possible.tex  index 1509f2c..affb86b 100644  --- a/a) As few classrooms as possible.tex  +++ b/a) As few classrooms as possible.tex 
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if i.start < j.finish  maxcol <- max(maxcol, len(collisions) + 1)  else  collisions.remove(j) collisions.removeFirst()  collisions.append(i)