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Leetcode
Easy
Arrays
Math
Plus One
Increment a non-negative integer represented as an array of digits and return the updated digit array.
Acceptance 100%
Problem Statement
You are given a non-negative integer represented as an array of decimal digits, where the most significant digit comes first. Add one to the integer and return the resulting array of digits.
The returned array should not contain leading zeros unless the number itself is zero.
Input Format
- A list of digits
digits, where each element is an integer from0to9. - The digits represent a non-negative integer in most-significant-digit first order.
Output Format
- Return a new list of digits representing the value
digits + 1.
Constraints
1 <= digits.length- Each
digits[i]is in the range[0, 9] digitsrepresents a valid non-negative integer without leading zeros, except possibly when the number is zero.
Examples
Sample cases returned by the problem API.
Example 1
Input
digits = [1,2,3]
Output
[1,2,4]
Explanation
123 + 1 = 124.
Example 2
Input
digits = [4,3,2,1]
Output
[4,3,2,2]
Explanation
4321 + 1 = 4322.
Show 1 more example
Example 3
Input
digits = [9]
Output
[1,0]
Explanation
9 + 1 = 10.
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