Level 1 · FoundationsBUILD YOUR INTUITION
Binary Search
A comparison proves that one half of the remaining candidates cannot contain the answer.
THE MENTAL MODELWhen should this come to mind?
A comparison proves that one half of the remaining candidates cannot contain the answer.
Sorted inputMonotonic predicateFirst feasible value What makes it work
Choose inclusive or half-open bounds and keep that convention throughout.
When to choose something else
Without sorted order or monotonicity, eliminating half the candidates is not justified.
See the pattern in action
Change the input. Follow the state. Make it yours.