Count Equal and Divisible Pairs in an Array
This problem involves counting pairs of elements that both have the same value and whose indices multiply to a multiple of k
. We can solve this by first finding pairs of elements with the same value and then checking if the product of their indices is divisible by k
.
Here’s the Python code:


In this solution, we initialize a counter count
to zero. We then iterate over the list nums
with a nested loop, where the inner loop starts from i+1
to avoid duplicate pairs and pairs with the same index.
For each pair (i, j)
, we check two conditions:
nums[i]
is equal tonums[j]
(they have the same value), and The product of the indices
i
andj
is divisible byk
.
If both conditions are met, we increment count
. After all pairs have been checked, we return count
, which is the number of pairs that meet the given criteria.