Array iku blok memory kontigo sing ngandhut elemen saka jenis sing padha, diindeks wiwit 0. Amarga elemen-elemen dumunung jejer-jejeran, alamat saka elemen i dihitung langsung minangka base + i * elementSize, menehi O(1) random access.
index: 0 1 2 3 4
+-----+-----+-----+-----+-----+
arr = | 10 | 20 | 30 | 40 | 50 |
+-----+-----+-----+-----+-----+
address: base +4 +8 +12 +16 (4-byte ints)
arr = [10, 20, 30, 40, 50]
x = arr[3] # O(1) — direct index math
arr.append(60) # amortized O(1) (dynamic array)
arr.insert(0, 5) # O(n) — shift every element right
arr.pop(0) # O(n) — shift every element left
| Operation | Time |
|---|---|
| Access by index | O(1) |
| Search (unsorted) | O(n) |
| Append (dynamic) | O(1) amortized |
| Insert/delete at front/middle | O(n) |
Array iku fondasi ing ngisor-e struktur paling - strings, hash tables, heaps, lan dynamic lists kabeh bangun sawerining dheweke.
Cache locality dheweke asring naggawe array "alon" ngalahake struktur "cepet" berbasis-pointer ing real benchmarks.