Add MinimumWaitingTime algorithm (#5794)

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;
+    }
+}

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<Arguments> 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));
+    }
+}