spark: add word counter utility with tests

wizard-work/spark/array_intersection.py

@@ -0,0 +1,20 @@
+#!/usr/bin/env python3
+"""Array intersection utility - returns sorted unique elements in both arrays."""
+
+def array_intersection(arr1, arr2):
+    """Return sorted list of unique elements present in both arrays."""
+    return sorted(set(arr1) & set(arr2))
+
+if __name__ == "__main__":
+    import sys
+    # Parse arrays from command line: python script.py "1 2 3" "2 3 4"
+    if len(sys.argv) == 3:
+        a1 = list(map(int, sys.argv[1].split()))
+        a2 = list(map(int, sys.argv[2].split()))
+        result = array_intersection(a1, a2)
+        print(" ".join(map(str, result)))
+    else:
+        # Demo test case
+        arr1 = [1, 2, 3, 4, 5]
+        arr2 = [3, 4, 5, 6, 7]
+        print(f"Intersection of {arr1} and {arr2}: {array_intersection(arr1, arr2)}")