bael-8350:implementation (eugenp#17186)

imsurajmishra · technoddy · web-flow · commit 71dcc56bc613 · 2024-08-09T20:51:43.000-05:00
* bael-8350:implementation

* bael-8350: feedback

---------

Co-authored-by: technoddy &lt;mail.technoddy@gmail.com&gt;
diff --git a/algorithms-modules/algorithms-miscellaneous-7/src/test/java/com/baeldung/algorithms/findmissingnumber/FindMissingNumberUnitTest.java b/algorithms-modules/algorithms-miscellaneous-7/src/test/java/com/baeldung/algorithms/findmissingnumber/FindMissingNumberUnitTest.java
@@ -2,8 +2,12 @@
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.BitSet;
+import java.util.Collections;
+import java.util.List;
+import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 
 import org.junit.jupiter.api.BeforeEach;
@@ -81,4 +85,30 @@ void givenIntegersArray_whenUseBitSetToFindMissingNumber_thenGetMissingNumber()
 
         assertEquals(3, missingNumber);
     }
+
+    @Test
+    void givenIntegersArrayWithMultipleMissingNumbers_whenUseBitSetToFindMultipleMissingNumbers_thenGetMultipleMissingNumbers() {
+        int[] numbersWithMultipleMissing = new int[] { 1, 5, 2, 8, 9 };
+        int N = Arrays.stream(numbersWithMultipleMissing)
+            .max()
+            .getAsInt();
+
+        BitSet allBitSet = new BitSet(N + 1);
+        IntStream.rangeClosed(1, N)
+            .forEach(allBitSet::set);
+
+        BitSet presentBitSet = new BitSet(N + 1);
+        Arrays.stream(numbersWithMultipleMissing)
+            .forEach(presentBitSet::set);
+
+        allBitSet.and(presentBitSet);
+
+        List<Integer> result = IntStream.rangeClosed(1, N)
+            .filter(i -> !allBitSet.get(i))
+            .boxed()
+            .sorted()
+            .collect(Collectors.toList());
+
+        assertEquals(result, Arrays.asList(3, 4, 6, 7));
+    }
 }
