For Complexity and tractability, questions may cover: polynomial and non-polynomial time complexity, Big O notations O(1), O(log n), O(n) , O(n^k), O(2^n), O(n!), and best-case, worst-case, and average-case time complexity, complexity classes (P, NP, NP-complete), solving complex problems (approximation algorithms / heuristics), algorithm design and optimisation, optimal solutions (Travelling Salesman / knapsack, etc.).  

For computer graphics, questions may cover: bitmap and vector graphics, matrices and transformations, line and circle algorithms (e.g. Bresenham's line algorithm, midpoint circle algorithm), image rendering (raytracing vs rasterisation), texture mapping, lighting, and lighting effects and reflections. 

For computer vision, questions may cover: noise, thresholding, edge detection, image processing for computer vision, applications in fields of obstacle detection (e.g. Lidar and stereo vision), feature extraction (e.g. Viola Jones, Haar-like features) and medical detection, and the application of techniques to medical diagnosis (e.g. convolutional neural networks, decision trees, and random forests).