add python version

python/intersection.py

@@ -0,0 +1,43 @@
+from typing import List
+
+
+def intersection(left: List[int], right: List[int]) -> List[int]:
+    result = []
+    for i in range(0, len(left)):
+        for j in range(0, len(right)):
+            if left[i] == right[j]:
+                result.append(left[i])
+                break
+
+    return result
+
+
+def intersection2(left: List[int], right: List[int]) -> List[int]:
+    result = []
+    for left_val in left:
+        for right_val in right:
+            if left_val == right_val:
+                result.append(left_val)
+                break
+
+    return result
+
+
+# silly to make intoa function but here we are
+def intersection3(left: List[int], right: List[int]) -> List[int]:
+    return [i for i in left if i in right]
+
+
+def main():
+    res = intersection([1, 2, 3, 4, 5], [5, 6, 7, 8, 9, 4])
+    res2 = intersection2([1, 2, 3, 4, 5], [5, 6, 7, 8, 9, 4, 5, 5, 5, 1, 2, 3, 4])
+    res3 = intersection3([1, 2, 3, 4, 5], [5, 6, 7, 8, 9, 4, 5, 5, 5, 1, 2, 3, 4])
+
+    # and the list comprehension
+    print(res)
+    print(res2)
+    print(res3)
+
+
+if __name__ == "__main__":
+    main()