Learning

Find a value in a sorted collection in O(log n) by repeatedly halving the search space.

A tree that keeps every left descendant smaller and every right descendant larger, giving O(log n) search, insert, and delete when balanced.

Before any data flows, a TCP client and server exchange three segments — SYN, SYN-ACK, ACK — to agree on starting sequence numbers and confirm both sides are ready.

Two ways to visit every reachable node in a graph — breadth-first spreads outward level by level, depth-first commits to one path and backtracks.

A complete binary tree, stored flat in an array, that keeps the smallest (or largest) element one O(log n) extraction away — the standard way to build a priority queue.

Turn exponential recursion into polynomial time by caching the answer to every subproblem the first time it's solved, so it's never recomputed.

Make the locally-best choice at every step, never reconsider it, and — for the specific class of problems where this provably reaches the global optimum — end up with the right answer in a single pass.

Find the shortest distance from one start node to every other node in a weighted graph, by always finalizing the nearest unvisited node next and relaxing its edges.