timetabling:
course sections assigned (1 row per student, 1 col per course):
1 2 2 2
2 1 2 2
2 2 1 2
2 2 1 2
1 2 2 2
1 2 2 2
1 2 2 2
1 2 2 2
1 2 2 2
2 2 1 2
2 2 2 1
1 2 2 2
2 2 2 1
1 2 2 2
2 1 2 2
2 2 1 2
2 1 2 2
2 2 2 1
2 2 2 1
2 2 1 2
times of each section (1 row per course, 1 col per section):
1 6 1
1 5 1
1 4 1
1 2 1
1 3 1
1 1 1
----------