How hard is LeetCode 2569. Handling Sum Queries After Update?

LeetCode 2569. Handling Sum Queries After Update is rated Hard on LeetCode.

What is the time complexity of LeetCode 2569. Handling Sum Queries After Update?

The Python solution on this page runs in O(n + m \times \log n).

What is the space complexity of LeetCode 2569. Handling Sum Queries After Update?

The Python solution on this page uses O(n) auxiliary space.

What topics does LeetCode 2569. Handling Sum Queries After Update cover?

LeetCode 2569. Handling Sum Queries After Update is tagged Segment Tree and Array on LeetCode.

Handling Sum Queries After Update — LeetCode 2569 Python Solution

HardSegment TreeArray

Problem: #2569
Reading time: 13 min
Source: leetcode.com

The problem

You are given two 0-indexed arrays nums1 and nums2 and a 2D array queries of queries. There are three types of queries: For a query of type 1, queries[i] = [1, l, r].

Example

Input: nums1 = [1,0,1], nums2 = [0,0,0], queries = [[1,1,1],[2,1,0],[3,0,0]]
Output: [3]
Explanation: After the first query nums1 becomes [1,1,1]. After the second query, nums2 becomes [1,1,1], so the answer to the third query is 3. Thus, [3] is returned.

Python solution

Python

class Node:
    def __init__(self):
        self.l = self.r = 0
        self.s = self.lazy = 0


class SegmentTree:
    def __init__(self, nums):
        self.nums = nums
        n = len(nums)
        self.tr = [Node() for _ in range(n << 2)]
        self.build(1, 1, n)

    def build(self, u, l, r):
        self.tr[u].l, self.tr[u].r = l, r
        if l == r:
            self.tr[u].s = self.nums[l - 1]
            return
        mid = (l + r) >> 1
        self.build(u << 1, l, mid)
        self.build(u << 1 | 1, mid + 1, r)
        self.pushup(u)

    def modify(self, u, l, r):
        if self.tr[u].l >= l and self.tr[u].r <= r:
            self.tr[u].lazy ^= 1
            self.tr[u].s = self.tr[u].r - self.tr[u].l + 1 - self.tr[u].s
            return
        self.pushdown(u)
        mid = (self.tr[u].l + self.tr[u].r) >> 1
        if l <= mid:
            self.modify(u << 1, l, r)
        if r > mid:
            self.modify(u << 1 | 1, l, r)
        self.pushup(u)

    def query(self, u, l, r):
        if self.tr[u].l >= l and self.tr[u].r <= r:
            return self.tr[u].s
        self.pushdown(u)
        mid = (self.tr[u].l + self.tr[u].r) >> 1
        res = 0
        if l <= mid:
            res += self.query(u << 1, l, r)
        if r > mid:
            res += self.query(u << 1 | 1, l, r)
        return res

    def pushup(self, u):
        self.tr[u].s = self.tr[u << 1].s + self.tr[u << 1 | 1].s

    def pushdown(self, u):
        if self.tr[u].lazy:
            mid = (self.tr[u].l + self.tr[u].r) >> 1
            self.tr[u << 1].s = mid - self.tr[u].l + 1 - self.tr[u << 1].s
            self.tr[u << 1].lazy ^= 1
            self.tr[u << 1 | 1].s = self.tr[u].r - mid - self.tr[u << 1 | 1].s
            self.tr[u << 1 | 1].lazy ^= 1
            self.tr[u].lazy ^= 1


class Solution:
    def handleQuery(
        self, nums1: List[int], nums2: List[int], queries: List[List[int]]
    ) -> List[int]:
        tree = SegmentTree(nums1)
        s = sum(nums2)
        ans = []
        for op, a, b in queries:
            if op == 1:
                tree.modify(1, a + 1, b + 1)
            elif op == 2:
                s += a * tree.query(1, 1, len(nums1))
            else:
                ans.append(s)
        return ans

Complexity

Measure	Complexity
Time	O(n + m \times \log n)
Space	O(n) auxiliary

Frequently asked questions

How hard is LeetCode 2569. Handling Sum Queries After Update?: LeetCode 2569. Handling Sum Queries After Update is rated Hard on LeetCode.
What is the time complexity of LeetCode 2569. Handling Sum Queries After Update?: The Python solution on this page runs in O(n + m \times \log n).
What is the space complexity of LeetCode 2569. Handling Sum Queries After Update?: The Python solution on this page uses O(n) auxiliary space.
What topics does LeetCode 2569. Handling Sum Queries After Update cover?: LeetCode 2569. Handling Sum Queries After Update is tagged Segment Tree and Array on LeetCode.