Problem Description
An array is considered special if every pair of its adjacent elements contains two numbers with different parity. You are given an array of integer nums and a 2D integer matrix queries, where for queries[i] = [from_i, to_i] your task is to check that subarray nums[from_i..to_i] is special or not. Return an array of booleans answer such that answer[i] is true if nums[from_i..to_i] is special.
Key Insights
- Each subarray must have adjacent elements with different parity (one even, one odd).
- A single adjacent pair of the same parity in any subarray invalidates it as special.
- Efficient checking for each query is crucial due to the potential size of the input.
Space and Time Complexity
Time Complexity: O(n + q) where n is the length of nums and q is the number of queries.
Space Complexity: O(1) if no additional data structures are used for storing results.
Solution
To determine if each queried subarray is special, we can iterate through the nums array and check the parity of adjacent elements. If we find any adjacent elements with the same parity, we can mark that range as not special. We will use a list to store the results for each query, and this will require a single pass through the range specified in each query.