From 79034fa6333ea6ab67a7c7400b6c016b32e6c97c Mon Sep 17 00:00:00 2001 From: Tanmay Singh Date: Sun, 13 Oct 2024 02:43:32 +0530 Subject: [PATCH] feat: Add Xs3Conversion algo with JUnit tests --- DIRECTORY.md | 2 + .../bitmanipulation/Xs3Conversion.java | 58 +++++++++++++++++ .../bitmanipulation/Xs3ConversionTest.java | 65 +++++++++++++++++++ 3 files changed, 125 insertions(+) create mode 100644 src/main/java/com/thealgorithms/bitmanipulation/Xs3Conversion.java create mode 100644 src/test/java/com/thealgorithms/bitmanipulation/Xs3ConversionTest.java diff --git a/DIRECTORY.md b/DIRECTORY.md index 30fa2cbee199..5bd095545196 100644 --- a/DIRECTORY.md +++ b/DIRECTORY.md @@ -46,6 +46,7 @@ * [SingleElement](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SingleElement.java) * [SwapAdjacentBits](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SwapAdjacentBits.java) * [TwosComplement](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/TwosComplement.java) + * [Xs3Conversion](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/Xs3Conversion.java) * ciphers * a5 * [A5Cipher](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/ciphers/a5/A5Cipher.java) @@ -677,6 +678,7 @@ * [SingleElementTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SingleElementTest.java) * [SwapAdjacentBitsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SwapAdjacentBitsTest.java) * [TwosComplementTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/TwosComplementTest.java) + * [Xs3ConversionTest](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/Xs3ConversionTest.java) * ciphers * a5 * [A5CipherTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/ciphers/a5/A5CipherTest.java) diff --git a/src/main/java/com/thealgorithms/bitmanipulation/Xs3Conversion.java b/src/main/java/com/thealgorithms/bitmanipulation/Xs3Conversion.java new file mode 100644 index 000000000000..b22abc0c04ff --- /dev/null +++ b/src/main/java/com/thealgorithms/bitmanipulation/Xs3Conversion.java @@ -0,0 +1,58 @@ +package com.thealgorithms.bitmanipulation; + +/** + * This class provides methods to convert between XS-3 (Excess-3) and binary. + * + * Excess-3, also called XS-3, is a binary-coded decimal (BCD) code in which each decimal digit is represented by its corresponding 4-bit binary value plus 3. + * + * For more information, refer to the + * Excess-3 Wikipedia page. + * + * Example usage: + * 
+ * int binary = Xs3Conversion.xs3ToBinary(0x4567);
+ * System.out.println("XS-3 0x4567 to binary: " + binary); // Output: 1234
+ *
+ * int xs3 = Xs3Conversion.binaryToXs3(1234);
+ * System.out.println("Binary 1234 to XS-3: " + Integer.toHexString(xs3)); // Output: 0x4567
+ *
+ */ +public final class Xs3Conversion { + private Xs3Conversion() { + } + /** + * Converts an XS-3 (Excess-3) number to binary. + * + * @param xs3 The XS-3 number. + * @return The corresponding binary number. + */ + public static int xs3ToBinary(int xs3) { + int binary = 0; + int multiplier = 1; + while (xs3 > 0) { + int digit = (xs3 & 0xF) - 3; // Extract the last 4 bits (one XS-3 digit) and subtract 3 + binary += digit * multiplier; + multiplier *= 10; + xs3 >>= 4; // Shift right by 4 bits to process the next XS-3 digit + } + return binary; + } + + /** + * Converts a binary number to XS-3 (Excess-3). + * + * @param binary The binary number. + * @return The corresponding XS-3 number. + */ + public static int binaryToXs3(int binary) { + int xs3 = 0; + int shift = 0; + while (binary > 0) { + int digit = (binary % 10) + 3; // Extract the last decimal digit and add 3 + xs3 |= (digit << (shift * 4)); // Shift the digit to the correct XS-3 position + binary /= 10; // Remove the last decimal digit + shift++; + } + return xs3; + } +} diff --git a/src/test/java/com/thealgorithms/bitmanipulation/Xs3ConversionTest.java b/src/test/java/com/thealgorithms/bitmanipulation/Xs3ConversionTest.java new file mode 100644 index 000000000000..2e3242decba0 --- /dev/null +++ b/src/test/java/com/thealgorithms/bitmanipulation/Xs3ConversionTest.java @@ -0,0 +1,65 @@ +package com.thealgorithms.bitmanipulation; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +import org.junit.jupiter.api.Test; + +/** + * Unit tests for the Xs3Conversion class. + */ +public class Xs3ConversionTest { + + /** + * Test the xs3ToBinary method with an XS-3 number. + */ + @Test + public void testXs3ToBinary() { + int binary = Xs3Conversion.xs3ToBinary(0x4567); + assertEquals(1234, binary); // XS-3 0x4567 should convert to binary 1234 + } + + /** + * Test the binaryToXs3 method with a binary number. + */ + @Test + public void testBinaryToXs3() { + int xs3 = Xs3Conversion.binaryToXs3(1234); + assertEquals(0x4567, xs3); // Binary 1234 should convert to XS-3 0x4567 + } + + /** + * Test the xs3ToBinary method with zero. + */ + @Test + public void testXs3ToBinaryZero() { + int binary = Xs3Conversion.xs3ToBinary(0x0); + assertEquals(0, binary); // XS-3 0x0 should convert to binary 0 + } + + /** + * Test the binaryToXs3 method with zero. + */ + @Test + public void testBinaryToXs3Zero() { + int xs3 = Xs3Conversion.binaryToXs3(0); + assertEquals(0x0, xs3); // Binary 0 should convert to XS-3 0x0 + } + + /** + * Test the xs3ToBinary method with a single digit XS-3 number. + */ + @Test + public void testXs3ToBinarySingleDigit() { + int binary = Xs3Conversion.xs3ToBinary(0x5); + assertEquals(2, binary); // XS-3 0x5 should convert to binary 2 + } + + /** + * Test the binaryToXs3 method with a single digit binary number. + */ + @Test + public void testBinaryToXs3SingleDigit() { + int xs3 = Xs3Conversion.binaryToXs3(2); + assertEquals(0x5, xs3); // Binary 2 should convert to XS-3 0x5 + } +}