Add solution to Leetcode #349 - intersection of two arrays

300-400q/349.py

@@ -0,0 +1,37 @@
+'''
+Given two arrays, write a function to compute their intersection.
+
+Examples
+--------
+Input: nums1 = [1,2,2,1], nums2 = [2,2]
+Output: [2]
+
+Input: nums1 = [4,9,5], nums2 = [9,4,9,8,4]
+Output: [9,4]
+'''
+
+class Solution:
+  def intersection(self, arrA: List[int], arrB: List[int]) -> List[int]:
+
+    arrA.sort()
+    arrB.sort()
+
+    intersection = []
+
+    aIndex = 0
+    bIndex = 0
+    recentOverlap = None
+
+    while aIndex < len(arrA) and bIndex < len(arrB):
+      if arrA[aIndex] > arrB[bIndex]:
+        bIndex += 1
+      elif arrA[aIndex] == arrB[bIndex]:
+        if arrB[bIndex] != recentOverlap: # skip duplicate overlapping elements
+          recentOverlap = arrB[bIndex]
+          intersection.append(recentOverlap)
+        bIndex += 1 # you could increment aIndex instead
+      else:
+        # arrA[aIndex] < arrB[bIndex]
+        aIndex += 1
+
+    return intersection

README.md

@@ -143,6 +143,7 @@ Python solution of problems from [LeetCode](https://leetcode.com/).
 |378|[Kth Smallest Element in a Sorted Matrix](https://leetcode.com/problems/kth-smallest-element-in-a-sorted-matrix) | [Python](./300-400q/378.py)|Medium|
 |361|[Bomb Enemy](https://leetcode.com/problems/bomb-enemy)|[Python](./300-400q/361.py)|Medium|
 |350|[Intersection of Two Arrays II](https://leetcode.com/problems/intersection-of-two-arrays-ii/) | [Python](./300-400q/350.py)|Easy|
+|349|[Intersection of Two Arrays](https://leetcode.com/problems/intersection-of-two-arrays/) | [Python](./300-400q/349.py) | Easy | 
 |347|[Top K Frequent Elements](https://leetcode.com/problems/top-k-frequent-elements/) | [Python](./300-400q/347.py)|Medium|
 |346|[Moving Average from Data Stream](https://leetcode.com/problems/moving-average-from-data-stream)|[Python](./300-400q/346.py)|Easy|
 |340|[Longest Substring with At Most K Distinct Characters](https://leetcode.com/problems/longest-substring-with-at-most-k-distinct-characters)|[Python](./300-400q/340.py)|Hard|