Added Intersection Of Sorted Arrays

shivam-maharshi · shivam-maharshi · commit ca1474e7aa9c · 2017-02-17T13:09:27.000-05:00
diff --git a/src/main/java/interview/google/IntersectionOfSortedArrays.java b/src/main/java/interview/google/IntersectionOfSortedArrays.java
@@ -0,0 +1,42 @@
+package interview.google;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+import org.junit.Test;
+
+import junit.framework.TestCase;
+
+/**
+ * Link: https://www.interviewbit.com/problems/intersection-of-sorted-arrays/
+ * 
+ * @author shivam.maharshi
+ */
+public class IntersectionOfSortedArrays extends TestCase {
+
+  @Test
+  public static void test() {
+    assertEquals(4, intersect(Arrays.asList(new Integer[]{1,2,3,3,4,5,6}), Arrays.asList(new Integer[] {0,1,3,4,5})).size());
+    assertEquals(1, intersect(Arrays.asList(new Integer[]{10000000}), Arrays.asList(new Integer[] {10000000})).size());
+  }
+  
+  public static ArrayList<Integer> intersect(final List<Integer> a, final List<Integer> b) {
+    ArrayList<Integer> r = new ArrayList<>();
+    if (a == null || a.size() == 0 || b == null || b.size() == 0)
+      return r;
+    int i =0, j =0;
+    while (i < a.size() && j < b.size()) {
+      if (a.get(i).intValue() == b.get(j).intValue()) {
+        r.add(a.get(i));
+        i ++;
+        j ++;
+      } else if (a.get(i) < b.get(j))
+        i++;
+      else
+        j++;
+    }
+    return r;
+  }
+
+}
