Program to find diameter with the given radius of a circle.

Given the radius of a circle, write a program to find the diameter of a circle.

Examples:

Input: r=4
Output: 8

Input: r=5
Output:10

Approach:

The diameter of a circle is simply twice the radius.

Here's how you could express this formula in a mathematical sense:

D= 2* r
r is radius and D is diameter of a circle

Below is the implementation of the code:

The Given radius of the circle is: 4
The diameter of the circle is : 8

Time Complexity: O(1), since there is one multiplication operation which takes constant time.
Auxiliary Space: O(1), since no extra space has been taken.