diff --git a/DIRECTORY.md b/DIRECTORY.md index 1ecacc3c395e..ebbb8ddc3110 100644 --- a/DIRECTORY.md +++ b/DIRECTORY.md @@ -27,6 +27,7 @@ * [ClearLeftmostSetBit](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/ClearLeftmostSetBit.java) * [CountLeadingZeros](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/CountLeadingZeros.java) * [CountSetBits](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/CountSetBits.java) + * [GrayCodeConversion](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/GrayCodeConversion.java) * [HighestSetBit](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/HighestSetBit.java) * [IndexOfRightMostSetBit](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/IndexOfRightMostSetBit.java) * [IsEven](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/IsEven.java) @@ -652,6 +653,7 @@ * [ClearLeftmostSetBitTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/ClearLeftmostSetBitTest.java) * [CountLeadingZerosTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/CountLeadingZerosTest.java) * [CountSetBitsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/CountSetBitsTest.java) + * [GrayCodeConversionTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/GrayCodeConversionTest.java) * [HighestSetBitTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/HighestSetBitTest.java) * [IndexOfRightMostSetBitTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/IndexOfRightMostSetBitTest.java) * [IsEvenTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/IsEvenTest.java) diff --git a/src/main/java/com/thealgorithms/bitmanipulation/GrayCodeConversion.java b/src/main/java/com/thealgorithms/bitmanipulation/GrayCodeConversion.java new file mode 100644 index 000000000000..83cd30c7d50a --- /dev/null +++ b/src/main/java/com/thealgorithms/bitmanipulation/GrayCodeConversion.java @@ -0,0 +1,44 @@ +package com.thealgorithms.bitmanipulation; + +/** + * Gray code is a binary numeral system where two successive values differ in only one bit. + * This is a simple conversion between binary and Gray code. + * Example: + * 7 -> 0111 -> 0100 -> 4 + * 4 -> 0100 -> 0111 -> 7 + * 0 -> 0000 -> 0000 -> 0 + * 1 -> 0001 -> 0000 -> 0 + * 2 -> 0010 -> 0011 -> 3 + * 3 -> 0011 -> 0010 -> 2 + * + * @author Hardvan + */ +public final class GrayCodeConversion { + private GrayCodeConversion() { + } + + /** + * Converts a binary number to Gray code. + * + * @param num The binary number. + * @return The corresponding Gray code. + */ + public static int binaryToGray(int num) { + return num ^ (num >> 1); + } + + /** + * Converts a Gray code number back to binary. + * + * @param gray The Gray code number. + * @return The corresponding binary number. + */ + public static int grayToBinary(int gray) { + int binary = gray; + while (gray > 0) { + gray >>= 1; + binary ^= gray; + } + return binary; + } +} diff --git a/src/test/java/com/thealgorithms/bitmanipulation/GrayCodeConversionTest.java b/src/test/java/com/thealgorithms/bitmanipulation/GrayCodeConversionTest.java new file mode 100644 index 000000000000..1fe792028dca --- /dev/null +++ b/src/test/java/com/thealgorithms/bitmanipulation/GrayCodeConversionTest.java @@ -0,0 +1,29 @@ +package com.thealgorithms.bitmanipulation; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +import org.junit.jupiter.api.Test; + +public class GrayCodeConversionTest { + + @Test + public void testBinaryToGray() { + assertEquals(7, GrayCodeConversion.binaryToGray(5)); // 101 -> 111 + assertEquals(4, GrayCodeConversion.binaryToGray(7)); // 111 -> 100 + assertEquals(1, GrayCodeConversion.binaryToGray(1)); // 001 -> 001 + } + + @Test + public void testGrayToBinary() { + assertEquals(5, GrayCodeConversion.grayToBinary(7)); // 111 -> 101 + assertEquals(4, GrayCodeConversion.grayToBinary(6)); // 110 -> 100 + assertEquals(1, GrayCodeConversion.grayToBinary(1)); // 001 -> 001 + } + + @Test + public void testBinaryGrayCycle() { + int binary = 9; // 1001 in binary + int gray = GrayCodeConversion.binaryToGray(binary); + assertEquals(binary, GrayCodeConversion.grayToBinary(gray)); // Should return to original binary + } +}