fix: test corrected

Author: mjk22071998

src/test/java/com/thealgorithms/graph/TopologicalSortDFSTest.java

@@ -1,11 +1,6 @@
 package com.thealgorithms.graph;
 
 import static org.junit.jupiter.api.Assertions.assertArrayEquals;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
-import java.util.HashMap;
-import java.util.Map;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -39,7 +34,7 @@ public void testMultipleDependencies() {
         int[] result = topologicalSortDFS.findOrder(numCourses, prerequisites);
 
         // Valid answers could be [0,1,2,3] or [0,2,1,3]
-        int[] expected = { 0, 2, 1, 3 };
+        int[] expected = { 0, 1, 2, 3 };
         assertArrayEquals(expected, result, "Valid topological order expected, e.g., [0,1,2,3] or [0,2,1,3].");
     }
 
@@ -66,4 +61,23 @@ public void testCycleGraph() {
 
         assertArrayEquals(expected, result, "Cycle detected, no valid course order.");
     }
+
+    @Test
+    public void testComplexGraph() {
+        // Complex example: 6 courses
+        // Dependencies: 5->2, 5->0, 4->0, 4->1, 2->3, 3->1
+        int numCourses = 6;
+        int[][] prerequisites = {
+                { 2, 5 },
+                { 0, 5 },
+                { 0, 4 },
+                { 1, 4 },
+                { 3, 2 },
+                { 1, 3 }
+        };
+        int[] result = topologicalSortDFS.findOrder(numCourses, prerequisites);
+        // Valid order: [5, 4, 2, 3, 1, 0]
+        int[] expected = { 5, 4, 0, 2, 3, 1 };
+        assertArrayEquals(expected, result, "Valid topological order expected such as [5, 4, 0, 2, 3, 1].");
+    }
 }