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Practice Substring XOR Queries

Read the task, work through the examples, and check your approach against the constraints. Use the original LeetCode task for coding and submissions.

Medium#2564
LeetCode Problem

Substring XOR Queries

ArrayHash TableStringBit Manipulation

Problem Statement

You are given a binary string s, and a 2D integer array queries where queries[i] = [firsti, secondi]. For the ith query, find the shortest substring of s whose decimal value, val, yields secondi when bitwise XORed with firsti. In other words, val ^ firsti == secondi. The answer to the ith query is the endpoints (0-indexed) of the substring [lefti, righti] or [-1, -1] if no such substring exists. If there are multiple answers, choose the one with the minimum lefti. Return an array ans where ans[i] = [lefti, righti] is the answer to the ith query. A substring is a contiguous non-empty sequence of characters within a string.

Source: Substring XOR Queries on LeetCode. Use the original task for its coding environment and submissions.

Examples

# Example 1

Input
s = "101101", queries = [[0,5],[1,2]]
Output
[[0,2],[2,3]]

# Example 2

Input
s = "0101", queries = [[12,8]]
Output
[[-1,-1]]

# Example 3

Input
s = "1", queries = [[4,5]]
Output
[[0,0]]

Constraints

1 <= s.length <= 10^4
s[i] is either '0' or '1'.
1 <= queries.length <= 10^5
0 <= firsti, secondi <= 10^9

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