Python: Find k number of pairs which consists of one element from the first array and one element from the second array

Python heap queue algorithm: Exercise-17 with Solution

You have two integer arrays sorted in ascending order and an integer k. Write a Python program to find k number of pairs (u, v) which consist of one element from the first array and one element from the second array using the heap queue algorithm.

Sample Solution:

Python Code:

import heapq
def k_Smallest_Pairs(nums1, nums2, k):
   queue = []
   def push(i, j):
       if i < len(nums1) and j < len(nums2):
           heapq.heappush(queue, [nums1[i] + nums2[j], i, j])
   push(0, 0)
   pairs = []
   while queue and len(pairs) < k:
       _, i, j = heapq.heappop(queue)
       pairs.append([nums1[i], nums2[j]])
       push(i, j + 1)
       if j == 0:
           push(i + 1, 0)
   return pairs
nums1 = [1,3,7]
nums2 = [2,4,6]
k = 2
result = k_Smallest_Pairs(nums1, nums2, k)
print(result)

Sample Output:

[[1, 2], [1, 4]]

Flowchart:

Python Code Editor:

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