Here are links to previous exams and solutions.
2018 Exam and solutions. Suggestion: do problems 1 and 4.
2016 Exam and solutions. Suggestion: do problems 1 and 3.
2015 Exam and solutions. Suggestion: do problem 3.
2014 Exam and solutions. Suggestion: do problems 1 and 3.
2013 Exam and solutions. Suggestion: do problems 1 and 3.
2012 Exam and solutions. Suggestion: do problems 2 and 4.