225 students in a class take an exam and no set of four students got the same marks. Suppose all the students got marks from 0 to 100 (integers only), what is the maximum number of students who got unique marks?

0-100 : 101 students
Students remaining = 225-101 = 124
Now since max 3 people can have same marks.
we have assigned 1 ,so 2 more can fit.
Therefore 124/2 = 62 (0-61)
and 101-62 = 39
Therefore 39 students got unique marks.
I think. :p