DSA · Arrays & Math · #137
Plus One
Module 79 · difficulty 2/5·⏱ 30:00starts on first keystroke
You are given a large integer represented as an integer array `digits`, where each `digits[i]` is the `i`-th digit of the integer. The digits are ordered from most significant to least significant in left-to-right order. The integer does not contain any leading zero, except the number `0` itself. Implement `plusOne(digits)` which increments the large integer by one and returns the resulting array of digits.
Examples
digits = [1,2,3]→[1,2,4]— The integer 123 plus one is 124.digits = [4,3,2,1]→[4,3,2,2]— The integer 4321 plus one is 4322.digits = [9]→[1,0]— 9 plus one is 10, which needs an extra digit.
Constraints
- · 1 <= digits.length <= 100
- · 0 <= digits[i] <= 9
- · digits has no leading zeros except for the number 0 itself.
Session phases
A · Clarify
B · Approach
C · Complexity
D · Edges
E · Code
F · Tradeoff
G · Score
Phase A — Clarify
Ask questions about input bounds, types, and edge constraints.
Ask the coach clarifying questions about the problem.
When you've covered this phase, advance to the next.