testing: added unit tests for the BinaryPow.binPow (#6386)

testing: added unit tests for the BinaryPow.binPow

Co-authored-by: Deniz Altunkapan <93663085+DenizAltunkapan@users.noreply.github.com>

Author: alxkm

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

@@ -13,4 +13,34 @@ void testBinPow() {
         assertEquals(729, BinaryPow.binPow(9, 3));
         assertEquals(262144, BinaryPow.binPow(8, 6));
     }
+
+    @Test
+    void testZeroExponent() {
+        assertEquals(1, BinaryPow.binPow(2, 0));
+        assertEquals(1, BinaryPow.binPow(100, 0));
+        assertEquals(1, BinaryPow.binPow(-5, 0));
+    }
+
+    @Test
+    void testZeroBase() {
+        assertEquals(0, BinaryPow.binPow(0, 5));
+        assertEquals(1, BinaryPow.binPow(0, 0));
+    }
+
+    @Test
+    void testOneBase() {
+        assertEquals(1, BinaryPow.binPow(1, 100));
+        assertEquals(1, BinaryPow.binPow(1, 0));
+    }
+
+    @Test
+    void testNegativeBase() {
+        assertEquals(-8, BinaryPow.binPow(-2, 3));
+        assertEquals(16, BinaryPow.binPow(-2, 4));
+    }
+
+    @Test
+    void testLargeExponent() {
+        assertEquals(1073741824, BinaryPow.binPow(2, 30));
+    }
 }