DATA STRUCTURES • ALGORITHMS

Array Insertion

Inserting an element into an array at a specific index. This often requires shifting subsequent elements to the right to maintain order.

Time

O(N) (Worst Case)

Space

O(1) (In-place)

Key Principle 1

Shifting required for internal indices

Key Principle 2

O(1) if inserted at the end

Key Principle 3

Requires overflow check

Key Principle 4

Preserves relative order

INSERTION_LAB
ARRAY:
Current Step
Inserting 25 at index 2. We must shift elements to make space.
Playback
Speed
Insertion Data ⠿
POS2
VALUE25
SIZE4
Shift Logic ⠿
1// Shift elements to the right
2for (int i = size - 1; i >= pos; i--) {
3    arr[i + 1] = arr[i];
4}
5arr[pos] = newValue;
6size++;
10
[0]
20
[1]
30
[2]
40
[3]
-
[4]

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