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Shubham Jadhav
Shubham Jadhav

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ODD-EVEN Number using Recursion in JS 🚀

Hello Guys, Today is this article we are taking about Recursion.
We are solving and understanding a problem by using Recursion in JavaScript.

👉 Problem :- Find odd-even number using Recursion ?

Let's start today's article...

• What is recursion?
=> Recursion mean calling itself till condition not true. A function call itself that's function called Recursive function.

• How to find odd even number in JavaScript?
=> We are finding odd-even number by dividing 2. When the reminder is 0 it's mean the number is even or reminder is 1, it is odd number. Right...

We are using same logic in today's solving problem using recursion but different.

👉 Let's start solving problems

• First we create a function and pass one parameter. As following 👇

img1

• We are using same logic as we use always to find odd even number but in this problem we are consider if the parameter's value is 0 it is even or if it's value is 1 it means number is odd.

• See following code to better understand, we are using if-else condition. 👇
img2

• Now time to use recursion function but before using recursion we simply decrease parameter 'num' value by 2.
Because odd and even number difference is 2 for example 1 and 3 difference is 2 and also 2 and 4 difference is 2. See below 👇
img3

• In the above code, in a line number 14 we are calling a function that's mean it will call itself till when given condition not true.

• Let's check the output 👇
img4

🙏 Thanks for reading...
👉 Stay with us for more....

Discussion (5)

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code913 profile image
code913

The post was good but there's an easier, faster way to do this

const odd_evenNum = num => num % 2 === 0 ? "even" : "odd";
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dev_shubham profile image
Shubham Jadhav Author

Thanks for reading...
I was solving by using recursion above problem. That's why it's long solution.

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pierrewahlberg profile image
Pierre Vahlberg

If you want to make a new article, going down each sub array in an array (branches of a tree) would probably be a more useful scenario as well as more illustrative to the naivity of depth/iterarions 🤟

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lukeshiru profile image
LUKESHIRU

Not to mention that the solution in the post will have a stack overflow with big numbers while yours will always work.

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jonrandy profile image
Jon Randy

The author could write another post on trampolining to show how to avoid this