LC 0004 [H] Median of Two Sorted Arrays
Code with Senpai edited this page Mar 15, 2022
·
4 revisions
https://www.youtube.com/watch?v=q6IEA26hvXc&ab_channel=NeetCode
class Solution:
def findMedianSortedArrays(self, nums1: List[int], nums2: List[int]) -> float:
A, B = nums1, nums2
total = len(nums1) + len(nums2)
half = total // 2
# O( log(min(n, m)) )
# A should be smaller
if len(B) < len(A):
A, B = B, A
l, r = 0, len(A) - 1
while True:
i = (l + r) // 2 # A
j = half - i - 2 # B, -2 for the 2 infinity sides
Aleft = A[i] if i >= 0 else float('-inf')
Aright = A[i+1] if (i+1) < len(A) else float('inf')
Bleft = B[j] if j >= 0 else float('-inf')
Bright = B[j+1] if (j+1) < len(B) else float('inf')
# partition is correct
if Aleft <= Bright and Bleft <= Aright:
# odd
if total % 2:
return min(Aright, Bright)
# even
else:
return (max(Aleft, Bleft) + min(Aright, Bright)) / 2
elif Aleft < Bright:
l = i + 1
elif Aleft > Bright:
r = i - 1
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