# Count pair in an array whose product is divisible by k in Python

In this article, we will learn how to count the pair in an array whose product is divisible by k in Python.

Examples

```Input: arr[] = {2, 3, 5, 8, 9}
k = 4
Output: 4
Explanation: (2, 8), (3, 8), (5, 8), (9, 8) these are the possible pair that are divisible by given k vaule.

Input: arr[] = {2, 1, 3}
k = 4
Output: No possible pairs```

## Number of pair in an array whose product is divisible by k in Python

1. We are going to solve this problem using two nested loops.

2. Declare a variable count to store the result.

3. Iterate the array from range 0 to n as an outer loop

• Iterate the array from the range i+1 to n as an inner loop
• Now check if (arr[i]*arr[j]%k == 0) then increase count 1.

4. Finally, return the count.

```def countPairs(arr, n, k):
count = 0
for i in range(n):
for j in range(i+1, n):
if (arr[i]*arr[j]%k == 0):
count += 1
return count

arr = [2, 3, 5, 8, 9, 7, 10, 12]
n = len(arr)
k = int(input("Enter the k value: "))
result = countPairs(arr, n, k)
if(result>0):
print("Number of pair in an array whose product is divisible by k is ",result)
else:
print("No possible pairs")```

Output

```Enter the k value: 4
Number of pair in an array whose product is divisible by k is 14

Enter the k value: 11
No possible pairs```