From f3fd7e639783a93011e17e525fabb53a67091c0d Mon Sep 17 00:00:00 2001 From: Hardik Pawar Date: Thu, 10 Oct 2024 20:23:27 +0530 Subject: [PATCH 1/3] feat: Add `BinaryPalindromeCheck` new algorithm with Junit tests --- .../BinaryPalindromeCheck.java | 43 +++++++++++++++++++ .../BinaryPalindromeCheckTest.java | 18 ++++++++ 2 files changed, 61 insertions(+) create mode 100644 src/main/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheck.java create mode 100644 src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java diff --git a/src/main/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheck.java b/src/main/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheck.java new file mode 100644 index 000000000000..0d6fd140c720 --- /dev/null +++ b/src/main/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheck.java @@ -0,0 +1,43 @@ +package com.thealgorithms.bitmanipulation; + +/** + * This class contains a method to check if the binary representation of a number is a palindrome. + *

+ * A binary palindrome is a number whose binary representation is the same when read from left to right and right to left. + * For example, the number 9 has a binary representation of 1001, which is a palindrome. + * The number 10 has a binary representation of 1010, which is not a palindrome. + *

+ * + * @author Hardvan + */ +public final class BinaryPalindromeCheck { + private BinaryPalindromeCheck() { + } + + /** + * Checks if the binary representation of a number is a palindrome. + * + * @param x The number to check. + * @return True if the binary representation is a palindrome, otherwise false. + */ + public static boolean isBinaryPalindrome(int x) { + int reversed = reverseBits(x); + return x == reversed; + } + + /** + * Helper function to reverse all the bits of an integer. + * + * @param x The number to reverse the bits of. + * @return The number with reversed bits. + */ + private static int reverseBits(int x) { + int result = 0; + while (x > 0) { + result <<= 1; + result |= (x & 1); + x >>= 1; + } + return result; + } +} diff --git a/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java b/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java new file mode 100644 index 000000000000..4aca1f0527f1 --- /dev/null +++ b/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java @@ -0,0 +1,18 @@ +package com.thealgorithms.bitmanipulation; + +import static org.junit.jupiter.api.Assertions.assertFalse; +import static org.junit.jupiter.api.Assertions.assertTrue; + +import org.junit.jupiter.api.Test; + +public class BinaryPalindromeCheckTest { + + @Test + public void testIsBinaryPalindrome() { + assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(9)); // 1001 is a palindrome + assertFalse(BinaryPalindromeCheck.isBinaryPalindrome(10)); // 1010 is not a palindrome + assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(0)); // 0 is a palindrome + assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(1)); // 1 is a palindrome + assertFalse(BinaryPalindromeCheck.isBinaryPalindrome(12)); // 1100 is not a palindrome + } +} From 742993c2044ef357ef701e78cbd39289cfa6ba1c Mon Sep 17 00:00:00 2001 From: Hardvan Date: Thu, 10 Oct 2024 14:53:46 +0000 Subject: [PATCH 2/3] Update directory --- DIRECTORY.md | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/DIRECTORY.md b/DIRECTORY.md index a1a53cb2926c..bf9974c41599 100644 --- a/DIRECTORY.md +++ b/DIRECTORY.md @@ -23,6 +23,7 @@ * [WordPatternMatcher](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/backtracking/WordPatternMatcher.java) * [WordSearch](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/backtracking/WordSearch.java) * bitmanipulation + * [BinaryPalindromeCheck](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheck.java) * [BitSwap](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/BitSwap.java) * [CountSetBits](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/CountSetBits.java) * [HighestSetBit](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/HighestSetBit.java) @@ -36,6 +37,8 @@ * [OnesComplement](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/OnesComplement.java) * [ReverseBits](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/ReverseBits.java) * [SingleBitOperations](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/bitmanipulation/SingleBitOperations.java) + * [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) * ciphers * a5 @@ -636,6 +639,7 @@ * [WordPatternMatcherTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/backtracking/WordPatternMatcherTest.java) * [WordSearchTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/backtracking/WordSearchTest.java) * bitmanipulation + * [BinaryPalindromeCheckTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java) * [BitSwapTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/BitSwapTest.java) * [CountSetBitsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/CountSetBitsTest.java) * [HighestSetBitTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/HighestSetBitTest.java) @@ -649,6 +653,8 @@ * [OnesComplementTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/OnesComplementTest.java) * [ReverseBitsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/ReverseBitsTest.java) * [SingleBitOperationsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/bitmanipulation/SingleBitOperationsTest.java) + * [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) * ciphers * a5 From c0a2ad66ce0f2a35697d00c9ae834d30807418f1 Mon Sep 17 00:00:00 2001 From: Hardik Pawar Date: Thu, 10 Oct 2024 20:24:49 +0530 Subject: [PATCH 3/3] Fix --- .../bitmanipulation/BinaryPalindromeCheckTest.java | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java b/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java index 4aca1f0527f1..ff41344266e4 100644 --- a/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java +++ b/src/test/java/com/thealgorithms/bitmanipulation/BinaryPalindromeCheckTest.java @@ -9,7 +9,7 @@ public class BinaryPalindromeCheckTest { @Test public void testIsBinaryPalindrome() { - assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(9)); // 1001 is a palindrome + assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(9)); // 1001 is a palindrome assertFalse(BinaryPalindromeCheck.isBinaryPalindrome(10)); // 1010 is not a palindrome assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(0)); // 0 is a palindrome assertTrue(BinaryPalindromeCheck.isBinaryPalindrome(1)); // 1 is a palindrome