# Check if LCM of array elements is divisible by a prime number or not

Given an array and a number k, the task is to find if LCM of the array is divisible by k or not.

Examples:

```Input : int[] a = {10, 20, 15, 25}
k = 3
Output : true

Input : int[] a = {24, 21, 45, 57, 36};
k = 23;
Output : false
```

## Recommended: Please try your approach on {IDE} first, before moving on to the solution.

One simple solution is to first find LCM of array elements, then check if LCM is divisible by k or not.

Here, without calculating the LCM of the number we can find that LCM of the an array of number is divisible by a prime number k or not. If any number of the array is divisible by prime number k, then the LCM of the number is also divisible by prime number k.

## C++

```// C++ program to find LCM of array of number is
// divisible by a prime number k or not
#include<iostream>
using namespace std;

// Function to check any number of
// array is divisible by k or not
bool func( int a[], int k, int n)
{
// If any array element is divisible
// by k, then LCM of whole array
// should also be divisible.
for (int i=0; i<n; i++)
if (a[i]%k == 0)
return true;
return false;
}

// Driver program
int main()
{
int a[] = {14, 27, 38, 76, 84};
int k = 19;
bool res = func(a, k, 5);
if(res)
cout<<"true";
else
cout<<"false";
return 0;
}

/* This code is contributed by Mr. Somesh Awasthi */
```

## Java

```// Java program to find LCM of array of number is
// divisible by a prime number k or not
import java.lang.*;
import java.util.*;

class LCM
{
// Function to check any number of array is
// divisible by k or not
static boolean func( int a[], int k)
{
// If any array element is divisible
// by k, then LCM of whole array
// should also be divisible.
for (int i=0; i<a.length; i++)
if (a[i]%k == 0)
return true;
return false;
}

// Driver program
public static void main(String args[])
{
int[] a = {14, 27, 38, 76, 84};
int k = 19;
boolean res = func(a, k);
System.out.println(res);
}
}```

Output:

``` true

```

This article is contributed by Pramod Kumar. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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