# Find the maximum angle at which we can tilt the bottle without spilling any water

• Difficulty Level : Expert
• Last Updated : 11 Aug, 2021

Given a water bottle with the shape of a rectangular prism whose base is a square of side x cm and height y cm, the task is to find the maximum angle at which we can tilt the bottle without spilling any water, when z cubic cm of water is poured into the bottle, and gradually tilt the bottle around one of the sides of the base.

Examples:

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```Input: x = 2, y = 2, z = 4
Output: 45.00000
Explanation:
This bottle has a cubic shape,
and it is half-full.
The water gets split when we tilt
the bottle more than 45 degrees.

Input: x = 12, y = 21, z = 10
Output: 89.78346```

Approach:
First of all, we need to know that the surface of the water is always parallel to the ground. So if the bottle tilts the water remain parallel to the ground.
Here we have 2 cases:-

1. When the water is less than half of the total volume of the bottle, Then we consider the lower right triangle formed by water inside the bottle and with the help of tangent inverse calculate the required angle.
2. When the water is greater than or equal to the total volume of the bottle, then we consider the upper right triangle formed by empty space inside the bottle. Now we can calculate the angle easily.

Below is the implementation of the above approach:

## C++

 `// C++ program to find the maximum angle``// at which we can tilt the bottle``// without spilling any water` `#include ``using` `namespace` `std;` `float` `find_angle(``int` `x, ``int` `y, ``int` `z)``{` `    ``// Now we have the volume``    ``// of rectangular prism a*a*b``    ``int` `volume = x * x * y;` `    ``float` `ans = 0;` `    ``// Now we have 2 cases!``    ``if` `(z < volume / 2) {` `        ``float` `d = (x * y * y) / (2.0 * z);` `        ``// Taking the tangent inverse of value d``        ``// As we want to take out the required angle``        ``ans = ``atan``(d);``    ``}``    ``else` `{` `        ``z = volume - z;``        ``float` `d = (2 * z) / (``float``)(x * x * x);` `        ``// Taking the tangent inverse of value d``        ``// As we want to take out the required angle``        ``ans = ``atan``(d);``    ``}` `    ``// As of now the angle is in radian.``    ``// So we have to convert it in degree.``    ``ans = (ans * 180) / 3.14159265;` `    ``return` `ans;``}` `int` `main()``{``    ``// Enter the Base square side length``    ``int` `x = 12;` `    ``// Enter the Height of rectangular prism``    ``int` `y = 21;` `    ``// Enter the Base square side length``    ``int` `z = 10;` `    ``cout << find_angle(x, y, z) << endl;``}`

## Java

 `// Java program to find the maximum angle``// at which we can tilt the bottle``// without spilling any water``class` `GFG``{``    ``static` `float` `find_angle(``int` `x,``                     ``int` `y, ``int` `z)``    ``{` `        ``// Now we have the volume``        ``// of rectangular prism a*a*b``        ``int` `volume = x * x * y;` `        ``float` `ans = ``0``;` `        ``// Now we have 2 cases!``        ``if` `(z < volume / ``2``)``        ``{``            ``float` `d = (``float``) ((x * y * y) / (``2.0` `* z));` `            ``// Taking the tangent inverse of value d``            ``// As we want to take out the required angle``            ``ans = (``float``) Math.atan(d);``        ``}``        ``else``        ``{``            ``z = volume - z;``            ``float` `d = (``2` `* z) / (``float``) (x * x * x);` `            ``// Taking the tangent inverse of value d``            ``// As we want to take out the required angle``            ``ans = (``float``) Math.atan(d);``        ``}` `        ``// As of now the angle is in radian.``        ``// So we have to convert it in degree.``        ``ans = (``float``) ((ans * ``180``) / ``3.14159265``);` `        ``return` `ans;``    ``}` `    ``// Driver Code``    ``public` `static` `void` `main(String[] args)``    ``{``        ``// Enter the Base square side length``        ``int` `x = ``12``;` `        ``// Enter the Height of rectangular prism``        ``int` `y = ``21``;` `        ``// Enter the Base square side length``        ``int` `z = ``10``;` `        ``System.out.print(find_angle(x, y, z) + ``"\n"``);``    ``}``}` `// This code is contributed by PrinciRaj1992`

## Python3

 `# Python3 program to find the maximum angle``# at which we can tilt the bottle``# without spilling any water``from` `math ``import` `*` `def` `find_angle(x, y, z) :` `    ``# Now we have the volume``    ``# of rectangular prism a*a*b``    ``volume ``=` `x ``*` `x ``*` `y;` `    ``ans ``=` `0``;` `    ``# Now we have 2 cases!``    ``if` `(z < volume ``/``/` `2``) :` `        ``d ``=` `(x ``*` `y ``*` `y) ``/` `(``2.0` `*` `z);` `        ``# Taking the tangent inverse of value d``        ``# As we want to take out the required angle``        ``ans ``=` `atan(d);` `    ``else` `:` `        ``z ``=` `volume ``-` `z;``        ``d ``=` `(``2` `*` `z) ``/` `(``float``)(x ``*` `x ``*` `x);` `        ``# Taking the tangent inverse of value d``        ``# As we want to take out the required angle``        ``ans ``=` `atan(d);``    ` `    ``# As of now the angle is in radian.``    ``# So we have to convert it in degree.``    ``ans ``=` `(ans ``*` `180``) ``/` `3.14159265``;` `    ``return` `round``(ans, ``4``);` `# Driver Code``if` `__name__ ``=``=` `"__main__"` `:` `    ``# Enter the Base square side length``    ``x ``=` `12``;` `    ``# Enter the Height of rectangular prism``    ``y ``=` `21``;` `    ``# Enter the Base square side length``    ``z ``=` `10``;` `    ``print``(find_angle(x, y, z));` `# This code is contributed by AnkitRai01`

## C#

 `// C# program to find the maximum angle``// at which we can tilt the bottle``// without spilling any water``using` `System;` `class` `GFG``{``    ``static` `float` `find_angle(``int` `x,``                     ``int` `y, ``int` `z)``    ``{` `        ``// Now we have the volume``        ``// of rectangular prism a*a*b``        ``int` `volume = x * x * y;` `        ``float` `ans = 0;` `        ``// Now we have 2 cases!``        ``if` `(z < volume / 2)``        ``{``            ``float` `d = (``float``) ((x * y * y) / (2.0 * z));` `            ``// Taking the tangent inverse of value d``            ``// As we want to take out the required angle``            ``ans = (``float``) Math.Atan(d);``        ``}``        ``else``        ``{``            ``z = volume - z;``            ``float` `d = (2 * z) / (``float``) (x * x * x);` `            ``// Taking the tangent inverse of value d``            ``// As we want to take out the required angle``            ``ans = (``float``) Math.Atan(d);``        ``}` `        ``// As of now the angle is in radian.``        ``// So we have to convert it in degree.``        ``ans = (``float``) ((ans * 180) / 3.14159265);` `        ``return` `ans;``    ``}` `    ``// Driver Code``    ``public` `static` `void` `Main(String[] args)``    ``{``        ``// Enter the Base square side length``        ``int` `x = 12;` `        ``// Enter the Height of rectangular prism``        ``int` `y = 21;` `        ``// Enter the Base square side length``        ``int` `z = 10;` `        ``Console.Write(find_angle(x, y, z) + ``"\n"``);``    ``}``}` `// This code is contributed by Rajput-Ji`

## Javascript

 ``
Output:
`89.7835`

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