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Leetcode
Medium
Arrays
Math
Amazon
Add To Array Form Of Integer

Add an integer to a number stored as an array of digits and return the result in the same format.

Acceptance 0%
Problem Statement

Add To Array Form Of Integer

You are given an integer represented as an array of digits num, where num[i] is the i-th digit of the number from most significant to least significant. You are also given a non-negative integer k.

Return the array-form of the sum num + k.

The result should also be returned as an array of digits in most-significant-first order.

This problem is about performing addition digit by digit, without converting the whole array-form number into a language-specific integer type.

Input Format

  • num: an array of decimal digits, most significant digit first
  • k: a non-negative integer

The task is to compute the decimal representation of num + k and return it as an array of digits.

Output Format

  • Return an array of digits representing the sum in most-significant-first order.

Constraints

  • 1 <= num.length
  • Each num[i] is a digit from 0 to 9
  • num does not contain leading zeros, except that the number 0 itself may appear as [0]
  • 0 <= k
  • The answer may be larger than standard fixed-width integer types, so carry-based addition is expected
Examples
Sample cases returned by the problem API.

Example 1

Input

num = [1,2,0,0], k = 34

Output

[1,2,3,4]

Explanation

1200 + 34 = 1234.

Example 2

Input

num = [2,7,4], k = 181

Output

[4,5,5]

Explanation

274 + 181 = 455.

Show 1 more example

Example 3

Input

num = [9,9,9,9,9,9,9,9,9,9], k = 1

Output

[1,0,0,0,0,0,0,0,0,0,0]

Explanation

A final carry can create a new most significant digit.

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