Linear Search
Linear search checks elements one by one until it finds the target or reaches the end.
Beginne mit diesem mentalen Modell
Linear search checks elements one by one until it finds the target or reaches the end.
So funktioniert es – ohne unnötigen Jargon
It needs no sorting or preprocessing.
Worst-case it examines every element, so time is O(n).
Lies den Algorithmus als Folge von Entscheidungen
Write the preconditions first (sorted? uniform? random access?).
Maintain a clear search interval/state.
Prove that each step makes progress toward termination.
Read a tiny input by hand and write down the state after every important operation. For Linear Search, the goal is to make the invariant visible rather than to memorize code.
function linearSearch(items, target) {
for (let i = 0; i < items.length; i++) {
if (items[i] === target) return i;
}
return -1;
}Lerne die Syntax nicht auswendig. Folge dem Zustand, der sich in jeder Zeile ändert, und verbinde ihn mit der oben beschriebenen Invariante.
O(n)
Do not quote this complexity mechanically. Ask which operation or input dimension it describes, then derive the cost from the loops, recursion depth, data-structure operations and any preprocessing assumptions.
Gut geeignet
- Match the algorithm to the structure and preprocessing state of the data.
Was typischerweise schiefgeht
- Violating preconditions.
- Boundary and termination bugs.
Struktur einer professionellen Antwort
Do not dismiss it as 'bad'. For small, unsorted or one-off searches it may be the simplest and correct choice.
What problem does Linear Search solve?
Linear search checks elements one by one until it finds the target or reaches the end.
Was sollte ich zur Komplexität erwähnen?
Its typical cost here is O(n), but a complete answer should connect that cost to the representation, input constraints and the dominant operations.
Was ist der häufigste Fehler?
Violating preconditions.