diff --git a/DIRECTORY.md b/DIRECTORY.md index aa34bf1a9532..e7a08a12abac 100644 --- a/DIRECTORY.md +++ b/DIRECTORY.md @@ -320,6 +320,7 @@ * [JobSequencing](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/greedyalgorithms/JobSequencing.java) * [MergeIntervals](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/greedyalgorithms/MergeIntervals.java) * [MinimizingLateness](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/greedyalgorithms/MinimizingLateness.java) + * [MinimumWaitingTime](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTime.java) * [StockProfitCalculator](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/greedyalgorithms/StockProfitCalculator.java) * io * [BufferedReader](https://github.com/TheAlgorithms/Java/blob/master/src/main/java/com/thealgorithms/io/BufferedReader.java) @@ -921,6 +922,7 @@ * [JobSequencingTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/greedyalgorithms/JobSequencingTest.java) * [MergeIntervalsTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/greedyalgorithms/MergeIntervalsTest.java) * [MinimizingLatenessTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/greedyalgorithms/MinimizingLatenessTest.java) + * [MinimumWaitingTimeTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTimeTest.java) * [StockProfitCalculatorTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/greedyalgorithms/StockProfitCalculatorTest.java) * io * [BufferedReaderTest](https://github.com/TheAlgorithms/Java/blob/master/src/test/java/com/thealgorithms/io/BufferedReaderTest.java) diff --git a/src/main/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTime.java b/src/main/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTime.java new file mode 100644 index 000000000000..2341bcdee9f7 --- /dev/null +++ b/src/main/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTime.java @@ -0,0 +1,37 @@ +package com.thealgorithms.greedyalgorithms; + +import java.util.Arrays; + +/** + * The MinimumWaitingTime class provides a method to calculate the minimum + * waiting time for a list of queries using a greedy algorithm. + * + * @author Hardvan + */ +public final class MinimumWaitingTime { + private MinimumWaitingTime() { + } + + /** + * Calculates the minimum waiting time for a list of queries. + * The function sorts the queries in non-decreasing order and then calculates + * the waiting time for each query based on its position in the sorted list. + * + * @param queries an array of integers representing the query times in picoseconds + * @return the minimum waiting time in picoseconds + */ + public static int minimumWaitingTime(int[] queries) { + int n = queries.length; + if (n <= 1) { + return 0; + } + + Arrays.sort(queries); + + int totalWaitingTime = 0; + for (int i = 0; i < n; i++) { + totalWaitingTime += queries[i] * (n - i - 1); + } + return totalWaitingTime; + } +} diff --git a/src/test/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTimeTest.java b/src/test/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTimeTest.java new file mode 100644 index 000000000000..64cb4b80f182 --- /dev/null +++ b/src/test/java/com/thealgorithms/greedyalgorithms/MinimumWaitingTimeTest.java @@ -0,0 +1,21 @@ +package com.thealgorithms.greedyalgorithms; + +import static org.junit.jupiter.api.Assertions.assertEquals; + +import java.util.stream.Stream; +import org.junit.jupiter.params.ParameterizedTest; +import org.junit.jupiter.params.provider.Arguments; +import org.junit.jupiter.params.provider.MethodSource; + +public class MinimumWaitingTimeTest { + + @ParameterizedTest + @MethodSource("provideTestCases") + public void testMinimumWaitingTime(int[] queries, int expected) { + assertEquals(expected, MinimumWaitingTime.minimumWaitingTime(queries)); + } + + private static Stream provideTestCases() { + return Stream.of(Arguments.of(new int[] {3, 2, 1, 2, 6}, 17), Arguments.of(new int[] {3, 2, 1}, 4), Arguments.of(new int[] {1, 2, 3, 4}, 10), Arguments.of(new int[] {5, 5, 5, 5}, 30), Arguments.of(new int[] {}, 0)); + } +}