How to provide test cases for a C++ program and what if QA dept. reject it?
This is an open-end interview question.
Given an array with 2 numbers are duplicated odd times and others duplicated even numbers, find the odd duplicated numbers. 

After designing a C++ program of sorting and scan O(n lgn) , I need to provide some test cases. 

What test cases do I need to provide ? 
What if QA department reject my bug fix proposal ? 

thanks
How to provide test cases for a C++ program and what if QA dept. reject it?
===

This is an open-end interview question.
Given an array with 2 numbers are duplicated odd times and others duplicated even numbers, find the odd duplicated numbers. 

After designing a C++ program of sorting and scan O(n lgn) , I need to provide some test cases. 

What test cases do I need to provide ? 
What if QA department reject my bug fix proposal ? 

thanks