Math and Geometry

Math and geometry problems test your ability to translate a visual or numerical pattern into clean algorithmic logic. Many of these problems have elegant solutions that depend on a single mathematical observation, such as the structure of matrix rotation or the periodicity of digit sums. Unlike the earlier stages, there is no dominant pattern here. Instead, you are developing the habit of looking for structure in a problem before reaching for a general algorithm. These problems are a good test of problem-solving maturity: can you find the insight, or do you default to brute force?