1213. Intersection of Three Sorted Arrays
Easy
Given three integer arrays arr1, arr2 and arr3 sorted in strictly increasing order, return a sorted array of only the integers that appeared in all three arrays.
Example 1:
Input: arr1 = [1,2,3,4,5], arr2 = [1,2,5,7,9], arr3 = [1,3,4,5,8] Output: [1,5] Explanation: Only 1 and 5 appeared in the three arrays.
Example 2:
Input: arr1 = [197,418,523,876,1356], arr2 = [501,880,1593,1710,1870], arr3 = [521,682,1337,1395,1764] Output: []
Constraints:
1 <= arr1.length, arr2.length, arr3.length <= 10001 <= arr1[i], arr2[i], arr3[i] <= 2000
class Solution:
def arraysIntersection(self, arr1: List[int], arr2: List[int], arr3: List[int]) -> List[int]:
# appears = []
# for item in arr1:
# if self.search(arr2, item):
# appears.append(item)
# app = []
# for item in appears:
# if self.search(arr3, item):
# app.append(item)
# return app
s1 = set(arr1)
s2 = set(arr2)
s3 = set(arr3)
return sorted((s1.intersection(s2)).intersection(s3))
# def search(self, nums, target):
# l, r = 0, len(nums)-1
# while l <= r:
# mid = l + (r-l)//2
# if nums[mid] == target:
# return True
# elif nums[mid] > target:
# r = mid - 1
# else:
# l = mid + 1
# return False