Available question text
Given an array of digits, repeatedly replace it by the array of adjacent pairwise sums modulo 10 until only one number remains and return that value. The core challenge is recognizing the result equals sum(nums[i] * C(n-1,i)) mod 10 (with n up to 1000), so compute that efficiently under modulo arithmetic.
Related questions
Continue with questions that share topics or the same question type.
- Find Sum of Array Product of Magical Sequences
Coding
- Find the K-Sum of an Array
Coding
- Find the Minimum Possible Sum of a Beautiful Array
Coding
- Given an integer array nums, find the contiguous subarray (containing at least one number) which has the largest sum and return its sum. Walk through Kadane's algorithm and explain the O(n) approach.
Coding
Sources · 1 reference
These records explain where the question appears. A company tag or candidate report does not guarantee a future interview question.
Hello Interview · 1 record
No company association
Leetcode 2221. Find Triangular Sum of an Array
Reported date not specified · 0 source reports
Source snapshot: Nov 12, 2026
View source