Count Array Pairs Divisible by K — LeetCode 2183 Python Solution
HardArrayMathNumber Theory
- Problem
- #2183
- Pattern
- Math and Number Theory
- Reading time
- 2 min
- Source
- leetcode.com
The problem
Given a 0-indexed integer array nums of length n and an integer k, return the number of pairs (i, j) such that: 0 <= i < j <= n - 1 and nums[i] * nums[j] is divisible by k.
Example
- Input
- nums = [1,2,3,4,5], k = 2
- Output
- 7
- Explanation
- The 7 pairs of indices whose corresponding products are divisible by 2 are
Complexity
| Measure | Complexity |
|---|---|
| Time | O(n) or O(1) |
| Space | O(1) auxiliary |
Pattern: Math and Number Theory
Find the closed form, the invariant, or the modular identity — and skip the loop entirely. LeetCode 2183. Count Array Pairs Divisible by K is filed here on both counts: the reference solution below belongs to the algorithm family this hub collects, and LeetCode tags it Math and Number Theory.
The math and number theory guide has the Python template for the pattern and the 485 LeetCode problems that use it.
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Frequently asked questions
- How hard is LeetCode 2183. Count Array Pairs Divisible by K?
- LeetCode 2183. Count Array Pairs Divisible by K is rated Hard on LeetCode.
- What topics does LeetCode 2183. Count Array Pairs Divisible by K cover?
- LeetCode 2183. Count Array Pairs Divisible by K is tagged Array, Math and Number Theory on LeetCode.