mirror of
https://gitee.com/coder-xiaomo/leetcode-problemset
synced 2025-01-10 18:48:13 +08:00
36 lines
1.3 KiB
HTML
36 lines
1.3 KiB
HTML
<p>Given a <strong>0-indexed</strong> integer array <code>nums</code> of length <code>n</code> and an integer <code>k</code>, return <em>the <strong>number of pairs</strong></em> <code>(i, j)</code> <em>such that:</em></p>
|
|
|
|
<ul>
|
|
<li><code>0 <= i < j <= n - 1</code> <em>and</em></li>
|
|
<li><code>nums[i] * nums[j]</code> <em>is divisible by</em> <code>k</code>.</li>
|
|
</ul>
|
|
|
|
<p> </p>
|
|
<p><strong>Example 1:</strong></p>
|
|
|
|
<pre>
|
|
<strong>Input:</strong> nums = [1,2,3,4,5], k = 2
|
|
<strong>Output:</strong> 7
|
|
<strong>Explanation:</strong>
|
|
The 7 pairs of indices whose corresponding products are divisible by 2 are
|
|
(0, 1), (0, 3), (1, 2), (1, 3), (1, 4), (2, 3), and (3, 4).
|
|
Their products are 2, 4, 6, 8, 10, 12, and 20 respectively.
|
|
Other pairs such as (0, 2) and (2, 4) have products 3 and 15 respectively, which are not divisible by 2.
|
|
</pre>
|
|
|
|
<p><strong>Example 2:</strong></p>
|
|
|
|
<pre>
|
|
<strong>Input:</strong> nums = [1,2,3,4], k = 5
|
|
<strong>Output:</strong> 0
|
|
<strong>Explanation:</strong> There does not exist any pair of indices whose corresponding product is divisible by 5.
|
|
</pre>
|
|
|
|
<p> </p>
|
|
<p><strong>Constraints:</strong></p>
|
|
|
|
<ul>
|
|
<li><code>1 <= nums.length <= 10<sup>5</sup></code></li>
|
|
<li><code>1 <= nums[i], k <= 10<sup>5</sup></code></li>
|
|
</ul>
|