Added twos complement tests

Author: Monk-AbhinayVerma

src/test/java/com/thealgorithms/bitmanipulation/TwosComplementTest.java

@@ -13,25 +13,25 @@ public class TwosComplementTest {
     @Test
     public void testTwosComplement_AllZeroes() {
         // Test with a binary number consisting entirely of zeroes
-        assertEquals("0000", TwosComplement.twosComplement("0000"));
-        assertEquals("000", TwosComplement.twosComplement("000"));
-        assertEquals("00", TwosComplement.twosComplement("00"));
-        assertEquals("0", TwosComplement.twosComplement("0"));
+        assertEquals("10000", TwosComplement.twosComplement("0000"));
+        assertEquals("1000", TwosComplement.twosComplement("000"));
+        assertEquals("100", TwosComplement.twosComplement("00"));
+        assertEquals("10", TwosComplement.twosComplement("0"));
     }
 
     @Test
     public void testTwosComplement_AllOnes() {
         // Test with a binary number consisting entirely of ones
-        assertEquals("11111", TwosComplement.twosComplement("11111")); // Extra '1' due to carry
-        assertEquals("1111", TwosComplement.twosComplement("1111"));
-        assertEquals("111", TwosComplement.twosComplement("111"));
-        assertEquals("11", TwosComplement.twosComplement("11"));
+        assertEquals("00001", TwosComplement.twosComplement("11111"));
+        assertEquals("0001", TwosComplement.twosComplement("1111"));
+        assertEquals("001", TwosComplement.twosComplement("111"));
+        assertEquals("01", TwosComplement.twosComplement("11"));
     }
 
     @Test
     public void testTwosComplement_MixedBits() {
         // Test with binary numbers with mixed bits
-        assertEquals("1110", TwosComplement.twosComplement("0001")); // 1's complement: 1110, then add 1: 1111
+        assertEquals("1111", TwosComplement.twosComplement("0001")); // 1's complement: 1110, then add 1: 1111
         assertEquals("1000", TwosComplement.twosComplement("0111")); // 1's complement: 1000
         assertEquals("11001", TwosComplement.twosComplement("00111")); // 1's complement: 11000, add 1: 11001
         assertEquals("011", TwosComplement.twosComplement("101")); // 1's complement: 010, add 1: 011
@@ -40,22 +40,15 @@ public void testTwosComplement_MixedBits() {
     @Test
     public void testTwosComplement_SingleBit() {
         // Test with single bit
-        assertEquals("1", TwosComplement.twosComplement("0"));
-        assertEquals("11", TwosComplement.twosComplement("1")); // 1's complement: 0, add 1: 1, carry generates extra
-                                                                // '1'
-    }
-
-    @Test
-    public void testTwosComplement_EmptyString() {
-        // Test with an empty string
-        assertEquals("", TwosComplement.twosComplement(""));
+        assertEquals("10", TwosComplement.twosComplement("0"));
+        assertEquals("11", TwosComplement.twosComplement("1"));
     }
 
     @Test
     public void testTwosComplement_WithLeadingZeroes() {
         // Test with leading zeroes in the input
         assertEquals("1111", TwosComplement.twosComplement("0001"));
-        assertEquals("100", TwosComplement.twosComplement("011"));
-        assertEquals("101", TwosComplement.twosComplement("010"));
+        assertEquals("101", TwosComplement.twosComplement("011"));
+        assertEquals("110", TwosComplement.twosComplement("010"));
     }
 }