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Problem

Given a large integer represented as an array of digits (most significant digit first), increment the integer by one and return the resulting array of digits.

Examples

Example 1

Input:digits = [1,2,3]

Output:[1,2,4]

Example 2

Input:digits = [9,9]

Output:[1,0,0]

Constraints

1 <= digits.length <= 100

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How to approach it: the Math & Geometry pattern

A grab-bag of problems solved with numeric or coordinate reasoning rather than a specific data structure — matrix manipulation, simulation, and basic number theory.

Look for this pattern when

The problem operates on a 2-D grid or matrix directly (rotate, transpose, traverse in a pattern).
There's no obvious "textbook" data structure — the problem is really about careful step-by-step simulation.

Read the full Math & Geometry guide →

Video walkthroughs

Original problem on LeetCode ↗