Find the unique mapping between elements of two same size arrays

Question

I was recently asked this question in an interview:

There are two arrays of size \'n\' each. One array has nuts, the other one has bolts. Each nut fits exactly one bolt

Answer 1

For formal analyses (including quicksort) see http://www.wisdom.weizmann.ac.il/~naor/PUZZLES/nuts_solution.html and http://compgeom.cs.uiuc.edu/~jeffe/teaching/algorithms/notes/05-nutsbolts.pdf