20 Dec 88. Merge Sorted Array
Posted at 18:37h in Coding 0 Comments
You are given two integer arrays
nums2, sorted in non-decreasing order, and two integers
n, representing the number of elements in
nums2 into a single array sorted in non-decreasing order.
The final sorted array should not be returned by the function, but instead be stored inside the array
nums1. To accommodate this,
nums1 has a length of
m + n, where the first
m elements denote the elements that should be merged, and the last
n elements are set to
0 and should be ignored.
nums2 has a length of
Input: nums1 = [1,2,3,0,0,0], m = 3, nums2 = [2,5,6], n = 3 Output: [1,2,2,3,5,6] Explanation: The arrays we are merging are [1,2,3] and [2,5,6]. The result of the merge is [1,2,2,3,5,6] with the underlined elements coming from nums1.
Input: nums1 = , m = 1, nums2 = , n = 0 Output:  Explanation: The arrays we are merging are  and . The result of the merge is .
Input: nums1 = , m = 0, nums2 = , n = 1 Output:  Explanation: The arrays we are merging are  and . The result of the merge is . Note that because m = 0, there are no elements in nums1. The 0 is only there to ensure the merge result can fit in nums1.
nums1.length == m + n
nums2.length == n
0 <= m, n <= 200
1 <= m + n <= 200
-109 <= nums1[i], nums2[j] <= 109
Follow up: Can you come up with an algorithm that runs in
O(m + n) time?
def merge(self, nums1: List[int], m: int, nums2: List[int], n: int) -> None:
Do not return anything, modify nums1 in-place instead.
tmp_nums1 = nums1[:m]
p1 = 0
p2 = 0
for p in range(m+n):
if p2>=n or (p1<m and tmp_nums1[p1]<= nums2[p2]):
nums1[p] = tmp_nums1[p1]
p1 = p1 + 1
nums1[p] = nums2[p2]
p2 = p2 + 1