DSA · Theory

Concatenation of two Linked Lists in O(1) time

Theory

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Concatenation of two Linked Lists in O(1) time

Concatenation of two Linked Lists in O(1) time is a DSA topic. In plain words you use it for a ticket queue node in a counter. Don’t start with a slogan — start with that picture.

Smallest example: head → next → …. Type it, run it, and say what you see. If you can do that from memory, you know Concatenation of two Linked Lists in O(1) time.

From the example next to this theory — Concatenation of two Linked Lists in O(1) time: dry-run [4, 1, 3].

Trap — losing the next pointer on delete. Fix that before you talk about advanced DSA.

Viva — what is Concatenation of two Linked Lists in O(1) time? Then show head → next → …. Then name the trap.

Diagram

  [10] → [20] → [30] → /
   head              tail

Exam tip

What is Concatenation of two Linked Lists in O(1) time? Show this: head → next → …. Trap: losing the next pointer on delete.

Example

# Concatenation of two Linked Lists in O(1) time
data = [4, 1, 3]
print("start", data)
if data[0] > data[1]:
    data[0], data[1] = data[1], data[0]
print("after one step", data)

Concatenation of two Linked Lists in O(1) time: dry-run [4, 1, 3]. Say the list after one step.

Short notes

DefConcatenation of two Linked Lists in O(1) time — a ticket queue node in a counter.
Rulehead → next → …
Traplosing the next pointer on delete
Usea counter

DSA · Theory

Concatenation of two Linked Lists in O(1) time

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Theory

282/810

Concatenation of two Linked Lists in O(1) time

Concatenation of two Linked Lists in O(1) time is a DSA topic. In plain words you use it for a ticket queue node in a counter. Don’t start with a slogan — start with that picture.

Smallest example: head → next → …. Type it, run it, and say what you see. If you can do that from memory, you know Concatenation of two Linked Lists in O(1) time.

From the example next to this theory — Concatenation of two Linked Lists in O(1) time: dry-run [4, 1, 3].

Trap — losing the next pointer on delete. Fix that before you talk about advanced DSA.

Viva — what is Concatenation of two Linked Lists in O(1) time? Then show head → next → …. Then name the trap.

Diagram

  [10] → [20] → [30] → /
   head              tail

Exam tip

What is Concatenation of two Linked Lists in O(1) time? Show this: head → next → …. Trap: losing the next pointer on delete.

Example

# Concatenation of two Linked Lists in O(1) time
data = [4, 1, 3]
print("start", data)
if data[0] > data[1]:
    data[0], data[1] = data[1], data[0]
print("after one step", data)

Concatenation of two Linked Lists in O(1) time: dry-run [4, 1, 3]. Say the list after one step.

Short notes

DefConcatenation of two Linked Lists in O(1) time — a ticket queue node in a counter.
Rulehead → next → …
Traplosing the next pointer on delete
Usea counter

Concatenation of two Linked Lists in O(1) time

Example

Short notes

Questions

Concatenation of two Linked Lists in O(1) time

Example

Short notes

Questions