CONCEPT BLOGS
Multi-phase guides with mental models, worked examples, diagrams, and real edge cases — the public form of Learnisim AI's conceptual learning. Read here; train it interactively in the app.
![Majority in [3, 2, 3] and in [2, 2, 1, 1, 1, 2, 2] overview diagram](/blogs/majority-element-boyer-moore-explained-tracing-3-2-3/diagrams/hero.svg)
Learn the Boyer-Moore Majority Vote Algorithm by tracing [3, 2, 3] and [2, 2, 1, 1, 1, 2, 2] using the intuitive tug-of-war cancellation mental model.
![Rotate [[1,2,3],[4,5,6],[7,8,9]] overview diagram](/blogs/rotate-matrix-90-clockwise-in-place-tracing-1-2-3-4-5-6-7-8-9/diagrams/hero.svg)
Learn how to rotate a 3×3 matrix [[1,2,3],[4,5,6],[7,8,9]] 90° clockwise in-place using transpose and reverse steps without extra memory.
![Zero [[1,1,1],[1,0,1],[1,1,1]] overview diagram](/blogs/set-matrix-zeroes-explained-in-place-markers-on-3-3-grid/diagrams/hero.svg)
Learn Set Matrix Zeroes using in-place markers. Trace the [[1,1,1],[1,0,1],[1,1,1]] example step-by-step and master the flag split edge case.
![Next permutation of [1, 3, 2] and of [3, 2, 1] overview diagram](/blogs/next-permutation-explained-finding-the-next-state-of-1-3-2/diagrams/hero.svg)
Trace the lexicographic pivot-and-reverse algorithm step-by-step using the sequences [1, 3, 2] and [3, 2, 1] to understand sequence rearrangement.
![gas=[1,2,3,4,5] cost=[3,4,5,1,2] overview diagram](/blogs/gas-station-circular-tour-explained-tracing-gas-1-2-3-4-5/diagrams/hero.svg)
Trace gas=[1,2,3,4,5] and cost=[3,4,5,1,2] to master the circular gas station tour problem using a greedy mental model in O(n) time.
![Find 0 in [4,5,6,7,0,1,2]; then 0 in [2,2,2,0,2] overview diagram](/blogs/binary-search-in-rotated-sorted-array-tracing-4-5-6-7-0-1-2/diagrams/hero.svg)
Master binary search in a rotated sorted array. Trace exact steps for [4,5,6,7,0,1,2] and [2,2,2,0,2], mastering sorted halves and duplicate edge cases.
