DSA · Theory

Merge Two Sorted Linked Lists

Theory

688/810

Merge Two Sorted Linked Lists

Merge Two Sorted Linked Lists 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 Merge Two Sorted Linked Lists.

From the example next to this theory — Merge Two Sorted Linked Lists: dry-run [4, 1, 3].

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

Viva — what is Merge Two Sorted Linked Lists? Then show head → next → …. Then name the trap.

Diagram

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

Exam tip

What is Merge Two Sorted Linked Lists? Show this: head → next → …. Trap: losing the next pointer on delete.

Example

# Merge Two Sorted Linked Lists
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)

Merge Two Sorted Linked Lists: dry-run [4, 1, 3]. Say the list after one step.

Short notes

DefMerge Two Sorted Linked Lists — a ticket queue node in a counter.
Rulehead → next → …
Traplosing the next pointer on delete
Usea counter

DSA · Theory

Merge Two Sorted Linked Lists

← All stacks

Theory

688/810

Merge Two Sorted Linked Lists

Merge Two Sorted Linked Lists 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 Merge Two Sorted Linked Lists.

From the example next to this theory — Merge Two Sorted Linked Lists: dry-run [4, 1, 3].

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

Viva — what is Merge Two Sorted Linked Lists? Then show head → next → …. Then name the trap.

Diagram

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

Exam tip

What is Merge Two Sorted Linked Lists? Show this: head → next → …. Trap: losing the next pointer on delete.

Example

# Merge Two Sorted Linked Lists
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)

Merge Two Sorted Linked Lists: dry-run [4, 1, 3]. Say the list after one step.

Short notes

DefMerge Two Sorted Linked Lists — a ticket queue node in a counter.
Rulehead → next → …
Traplosing the next pointer on delete
Usea counter

Merge Two Sorted Linked Lists

Example

Short notes

Questions

Merge Two Sorted Linked Lists

Example

Short notes

Questions