diff --git a/pom.xml b/pom.xml index d58039ee7a35..22c60f0ed72b 100644 --- a/pom.xml +++ b/pom.xml @@ -1,7 +1,7 @@ + xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" + xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4.0.0 com.thealgorithms Java @@ -123,9 +123,9 @@ - com.puppycrawl.tools - checkstyle - 10.18.2 + com.puppycrawl.tools + checkstyle + 10.18.2 diff --git a/src/main/java/com/thealgorithms/slidingwindow/LongestSubarrayWithSumLessOrEqualToK.java b/src/main/java/com/thealgorithms/slidingwindow/LongestSubarrayWithSumLessOrEqualToK.java new file mode 100644 index 000000000000..052cd2e00f61 --- /dev/null +++ b/src/main/java/com/thealgorithms/slidingwindow/LongestSubarrayWithSumLessOrEqualToK.java @@ -0,0 +1,48 @@ +package com.thealgorithms.slidingwindow; + +/** + * The Longest Subarray with Sum Less Than or Equal to k algorithm finds the length + * of the longest subarray whose sum is less than or equal to a given value k. + * + *

+ * Worst-case performance O(n) + * Best-case performance O(n) + * Average performance O(n) + * Worst-case space complexity O(1) + * + * @author (https://github.com/Chiefpatwal) + */ +public final class LongestSubarrayWithSumLessOrEqualToK { + + // Prevent instantiation + private LongestSubarrayWithSumLessOrEqualToK() { + } + + /** + * This method finds the length of the longest subarray with a sum less than or equal to k. + * + * @param arr is the input array + * @param k is the maximum sum allowed + * @return the length of the longest subarray with sum less than or equal to k + */ + public static int longestSubarrayWithSumLEK(int[] arr, int k) { + int maxLength = 0; // To store the maximum length found + int currentSum = 0; // To store the current sum of the window + int left = 0; // Left index of the sliding window + + for (int right = 0; right < arr.length; right++) { + currentSum += arr[right]; // Expand the window to the right + + // Shrink the window from the left if the current sum exceeds k + while (currentSum > k && left <= right) { + currentSum -= arr[left]; // Remove the leftmost element + left++; // Move the left index to the right + } + + // Update maxLength if the current window is valid + maxLength = Math.max(maxLength, right - left + 1); + } + + return maxLength; // Return the maximum length found + } +} diff --git a/src/test/java/com/thealgorithms/slidingwindow/LongestSubarrayWithSumLessOrEqualToKTest.java b/src/test/java/com/thealgorithms/slidingwindow/LongestSubarrayWithSumLessOrEqualToKTest.java new file mode 100644 index 000000000000..da282ab35ef3 --- /dev/null +++ b/src/test/java/com/thealgorithms/slidingwindow/LongestSubarrayWithSumLessOrEqualToKTest.java @@ -0,0 +1,22 @@ +package com.thealgorithms.slidingwindow; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +import org.junit.jupiter.api.Test; + +/** + * Unit tests for the LongestSubarrayWithSumLessOrEqualToK algorithm. + */ +public class LongestSubarrayWithSumLessOrEqualToKTest { + + /** + * Tests for the longest subarray with a sum less than or equal to k. + */ + @Test + public void testLongestSubarrayWithSumLEK() { + assertEquals(3, LongestSubarrayWithSumLessOrEqualToK.longestSubarrayWithSumLEK(new int[] {1, 2, 3, 4}, 6)); // {1, 2, 3} + assertEquals(4, LongestSubarrayWithSumLessOrEqualToK.longestSubarrayWithSumLEK(new int[] {1, 2, 3, 4}, 10)); // {1, 2, 3, 4} + assertEquals(2, LongestSubarrayWithSumLessOrEqualToK.longestSubarrayWithSumLEK(new int[] {5, 1, 2, 3}, 5)); // {5} + assertEquals(0, LongestSubarrayWithSumLessOrEqualToK.longestSubarrayWithSumLEK(new int[] {1, 2, 3}, 0)); // No valid subarray + } +}