Added volume of a torus (#7294)

* Added volume of a torus

Added function calculation the volume of a torus according to the formula:
V = 2 * pi^2 * R * r^2
where R is the major radius and r is the minor radius of the torus.

* Added test for torus volume

Author: kvadrik

src/main/java/com/thealgorithms/maths/Volume.java

@@ -114,4 +114,15 @@ public static double volumeFrustumOfCone(double r1, double r2, double height) {
     public static double volumeFrustumOfPyramid(double upperBaseArea, double lowerBaseArea, double height) {
         return (upperBaseArea + lowerBaseArea + Math.sqrt(upperBaseArea * lowerBaseArea)) * height / 3;
     }
+
+    /**
+     * Calculate the volume of a torus.
+     *
+     * @param majorRadius major radius of a torus
+     * @param minorRadius minor radius of a torus
+     * @return volume of the torus
+     */
+    public static double volumeTorus(double majorRadius, double minorRadius) {
+        return 2 * Math.PI * Math.PI * majorRadius * minorRadius * minorRadius;
+    }
 }

src/test/java/com/thealgorithms/maths/VolumeTest.java

@@ -38,5 +38,8 @@ public void volume() {
 
         /* test pyramid frustum */
         assertEquals(140.0, Volume.volumeFrustumOfPyramid(6, 24, 10));
+
+        /* test torus */
+        assertEquals(39.47841760435743, Volume.volumeTorus(2, 1));
     }
 }