1027. Sum of Even Numbers After Queries
My accepted Python solution to LeetCode problem 1027, Sum of Even Numbers After Queries, running in 13ms.
- Difficulty: Medium
- Python
- Runtime 13ms
- Memory 22.6MB
- Updated
Read the problem on LeetCode View on GitHub
The problem statement is LeetCode’s and stays on their site. What follows is my accepted solution.
Python
Accepted on LeetCode — runtime 13ms, memory 22.6MB, accepted 2026-01-02.
class Solution:
def sumEvenAfterQueries(self, nums: List[int], queries: List[List[int]]) -> List[int]:
# Calculate initial sum of even numbers
even_sum = sum(x for x in nums if x % 2 == 0)
result = []
for val, index in queries:
# Remove old value from even_sum if it was even
if nums[index] % 2 == 0:
even_sum -= nums[index]
# Update the value
nums[index] += val
# Add new value to even_sum if it's even
if nums[index] % 2 == 0:
even_sum += nums[index]
result.append(even_sum)
return result