Skip to content
Related Articles
Largest sphere that can be inscribed inside a cube
• Last Updated : 17 Mar, 2021

Given here is a cube of side length a, the task is to find the biggest sphere that can be inscribed within it.
Examples:

```Input: a = 4
Output: 2

Input: a = 5
Output: 2.5``` Approach

From the 2d diagram it is clear that, 2r = a
where, a = side of the cube
r = radius of the sphere
so r = a/2.

Below is the implementation of the above approach:

## C++

 `// C++ Program to find the biggest sphere``// inscribed within a cube``#include ``using` `namespace` `std;` `// Function to find the radius of the sphere``float` `sphere(``float` `a)``{` `    ``// side cannot be negative``    ``if` `(a < 0)``        ``return` `-1;` `    ``// radius of the sphere``    ``float` `r = a / 2;` `    ``return` `r;``}` `// Driver code``int` `main()``{``    ``float` `a = 5;``    ``cout << sphere(a) << endl;` `    ``return` `0;``}`

## Java

 `// Java Program to find the biggest sphere``// inscribed within a cube` `class` `GFG{``// Function to find the radius of the sphere``static` `float` `sphere(``float` `a)``{` `    ``// side cannot be negative``    ``if` `(a < ``0``)``        ``return` `-``1``;` `    ``// radius of the sphere``    ``float` `r = a / ``2``;` `    ``return` `r;``}` `// Driver code``public` `static` `void` `main(String[] args)``{``    ``float` `a = ``5``;``    ``System.out.println(sphere(a));` `}``}``// This code is contributed by mits`

## Python3

 `# Python 3 Program to find the biggest``# sphere inscribed within a cube` `# Function to find the radius``# of the sphere``def` `sphere(a):``    ` `    ``# side cannot be negative``    ``if` `(a < ``0``):``        ``return` `-``1` `    ``# radius of the sphere``    ``r ``=` `a ``/` `2` `    ``return` `r` `# Driver code``if` `__name__ ``=``=` `'__main__'``:``    ``a ``=` `5``    ``print``(sphere(a))` `# This code is contributed``# by SURENDRA_GANGWAR`

## C#

 `// C# Program to find the biggest``// sphere inscribed within a cube``using` `System;` `class` `GFG``{``// Function to find the radius``// of the sphere``static` `float` `sphere(``float` `a)``{` `    ``// side cannot be negative``    ``if` `(a < 0)``        ``return` `-1;` `    ``// radius of the sphere``    ``float` `r = a / 2;` `    ``return` `r;``}` `// Driver code``static` `public` `void` `Main ()``{``    ``float` `a = 5;``    ``Console.WriteLine(sphere(a));``}``}` `// This code is contributed by ajit`

## PHP

 ``

## Javascript

 ``
Output:
`2.5`

Attention reader! Don’t stop learning now. Get hold of all the important DSA concepts with the DSA Self Paced Course at a student-friendly price and become industry ready.  To complete your preparation from learning a language to DS Algo and many more,  please refer Complete Interview Preparation Course.

In case you wish to attend live classes with industry experts, please refer Geeks Classes Live

My Personal Notes arrow_drop_up