# DataWeave Interview Question: Find If Prime Number

### This article will help you practice your DataWeave skills in MuleSoft. We're going to find out if an input number is prime or not.

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Join For FreeA prime number is a number that is greater than 1 and divided by 1 or itself. In other words, prime numbers can't be divided by other numbers than themselves or 1. For example 2, 3, 5, 7, 11, 13, 17, 19, 23.... are the prime numbers.

Note: Please use 3 or greater than 3 for this logic.

**Input Payload:**

`xxxxxxxxxx`

`7`

**Output Result:**

`xxxxxxxxxx`

`"7 is prime number"`

In Step 1, we will apply a map starting from 2 till (payload - 1).

After that, we will use the mod operator to check reminders of payload by item.

**Step 1 Code:**

`xxxxxxxxxx`

`%dw 2.0`

`output application/json`

`---`

`(2 to payload-1) map ((item, index) -> payload mod item)`

**Step 1 Output:**

`xxxxxxxxxx`

`[`

` 1,`

` 1,`

` 3,`

` 2,`

` 1`

`]`

In Step 2, we will use an if statement and check whether the output array of our previous step contains 0 or not.

If 0 is present it means our payload is completely divided by another number and hence it is not a prime number.

If 0 is not present it means our payload is not completely divided by another number and hence it is a prime number.

**Final Code:**

`xxxxxxxxxx`

`%dw 2.0`

`output application/json`

`---`

`if(((2 to payload-1) map ((item, index) -> payload mod item) contains 0) == true) payload ++ " is not prime number" else payload ++ " is prime number"`

**Output:**

`xxxxxxxxxx`

`"7 is prime number"`

Hope this helps improve your DataWeave skills. I am not an expert on DataWeave. I am just sharing what I can solve. Comments are welcome. Thanks.

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