Coding Patterns

Two Pointers

Abstract Idea:

• Use two pointers (or indices) to traverse data from one or both ends, often to find a condition involving pairs or subsequences.

Pattern:

• You’re comparing elements from two places (beginning & end, or two sequences).
• You’re told to find pairs or triplets.
• Problem involves sorted data or linked list.

Problems:

• 1768. Merge Strings Alternately

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String: Unequal length handling

Abstract Idea:

• One part of the input runs out before the other — the solution must gracefully handle incomplete data or imbalanced structure.

Pattern:

• You’re merging, comparing or aligning multiple structures of different sizes.
• One side might finish early or the strings “may not be the same length”.

Problems:

• 1768. Merge Strings Alternately

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