Question

I normally ask this question in a interview for tester. Our software is really complex, has GUI and backend component. We require the tester to be good in analytical and can think out of the box. In this context, is the following question good to be asked or is it too complex/bad/ugly? Also our requirement is that the tester should be experienced.
The Question
There is a software named as Circles finding software. This software takes as input a Black or white image (the pixel is either black or white). If there is a circle in the image it will highlight the border in the red color and output the image, or else it will output the same image. It is supposed to find all the circles that a human can find in the image. So what all tests will you run on this software? By test I mean what all images you will pass to test it’s working. Please draw the images.

Answer 1

I think that question is fine as a “lead off” question – by that I would expect a viable candidate to come back with some questions for clarification – such as:

1. How close do two concentric circles need to be before they are no longer considered different circles?
2. How should a partial circle – that is, one which intersects the boundary of the image – be considered?
3. How “circular” does a circle have to be – are ellipses or ovoids considered “circles”?

You are looking for someone who can think about the underlying problem and tasks.