Cleanup perfect_cube.rs (TheAlgorithms#655)

Author: vil02

src/math/mod.rs

@@ -134,7 +134,7 @@ pub use self::modular_exponential::{mod_inverse, modular_exponential};
 pub use self::newton_raphson::find_root;
 pub use self::nthprime::nthprime;
 pub use self::pascal_triangle::pascal_triangle;
-pub use self::perfect_cube::{perfect_cube, perfect_cube_binary_search};
+pub use self::perfect_cube::perfect_cube_binary_search;
 pub use self::perfect_numbers::perfect_numbers;
 pub use self::perfect_square::perfect_square;
 pub use self::perfect_square::perfect_square_binary_search;

src/math/perfect_cube.rs

@@ -1,15 +1,7 @@
-pub fn perfect_cube(n: i32) -> bool {
-    // Calculate the cube root using floating-point arithmetic.
-    let val = (n as f64).powf(1.0 / 3.0);
-    // Check if the cube of the cube root equals the original number.
-    (val * val * val) == (n as f64)
-}
-
 // Check if a number is a perfect cube using binary search.
 pub fn perfect_cube_binary_search(n: i64) -> bool {
-    // Handle negative numbers, as cube roots are not defined for negatives.
     if n < 0 {
-        return false;
+        return perfect_cube_binary_search(-n);
     }
 
     // Initialize left and right boundaries for binary search.
@@ -39,17 +31,31 @@ pub fn perfect_cube_binary_search(n: i64) -> bool {
 mod tests {
     use super::*;
 
-    #[test]
-    fn test_perfect_cube() {
-        assert!(perfect_cube_binary_search(27));
-        assert!(!perfect_cube_binary_search(4));
+    macro_rules! test_perfect_cube {
+        ($($name:ident: $inputs:expr,)*) => {
+        $(
+            #[test]
+            fn $name() {
+                let (n, expected) = $inputs;
+                assert_eq!(perfect_cube_binary_search(n), expected);
+                assert_eq!(perfect_cube_binary_search(-n), expected);
+            }
+        )*
+        }
     }
 
-    #[test]
-    fn test_perfect_cube_binary_search() {
-        assert!(perfect_cube_binary_search(27));
-        assert!(perfect_cube_binary_search(64));
-        assert!(!perfect_cube_binary_search(4));
-        assert!(!perfect_cube_binary_search(-8));
+    test_perfect_cube! {
+        num_0_a_perfect_cube: (0, true),
+        num_1_is_a_perfect_cube: (1, true),
+        num_27_is_a_perfect_cube: (27, true),
+        num_64_is_a_perfect_cube: (64, true),
+        num_8_is_a_perfect_cube: (8, true),
+        num_2_is_not_a_perfect_cube: (2, false),
+        num_3_is_not_a_perfect_cube: (3, false),
+        num_4_is_not_a_perfect_cube: (4, false),
+        num_5_is_not_a_perfect_cube: (5, false),
+        num_999_is_not_a_perfect_cube: (999, false),
+        num_1000_is_a_perfect_cube: (1000, true),
+        num_1001_is_not_a_perfect_cube: (1001, false),
     }
 }