How do you solve Find the Distance Value Between Two Arrays on LeetCode?

Find the Distance Value Between Two Arrays (LeetCode #1385) can be solved using Brute Force or Optimal Solution. The optimal approach is Optimal Solution with O(n log n + m log m) time complexity and O(1) space complexity. Key insight: Sorting arr2 allows for efficient searching of closest elements.

What is the time complexity of Find the Distance Value Between Two Arrays?

The optimal solution for Find the Distance Value Between Two Arrays runs in O(n log n + m log m) time and uses O(1) space. The sorting of arr2 takes O(m log m), and for each element in arr1, we perform a binary search which takes O(log m), leading to an overall complexity of O(n log n + m log m).

What is the brute force solution for Find the Distance Value Between Two Arrays?

The brute force approach for Find the Distance Value Between Two Arrays is Brute Force, with O(n²) time complexity and O(1) space complexity. The brute force approach checks each element in arr1 against every element in arr2 to see if the absolute difference is within the allowed distance d. This is straightforward but inefficient. The optimal Optimal Solution approach improves this to O(n log n + m log m).

What algorithm or data structure is used to solve Find the Distance Value Between Two Arrays?

Find the Distance Value Between Two Arrays uses the following concepts: Array, Two Pointers, Binary Search, Sorting. The recommended patterns to study are: Binary Search, Sorting.

What are the interview tips for Find the Distance Value Between Two Arrays?

Always consider edge cases, such as when d is 0. Explain your thought process clearly while coding, especially when transitioning from brute force to optimal solutions. Practice binary search problems to become comfortable with its application.

What are common mistakes when solving Find the Distance Value Between Two Arrays?

Not sorting arr2 before performing binary search. Confusing the index returned by binary search, especially when the element is not found.

#1385

Find the Distance Value Between Two Arrays

Easy

ArrayTwo PointersBinary SearchSortingBinary SearchSorting

LeetCode ↗

Approaches

Brute ForceOptimal

Complexity Comparison

	Brute Force	Optimal Solution★
Time	O(n²)	O(n log n + m log m)
Space	O(1)	O(1)

💡

Intuition

Time O(n log n + m log m)Space O(1)

By sorting arr2 and using binary search, we can efficiently find the closest elements to each element in arr1. This reduces the number of comparisons significantly.

⚙️

Algorithm

6 steps

1Step 1: Sort arr2.
2Step 2: Initialize a counter to zero for counting distance values.
3Step 3: For each element in arr1, use binary search to find the position of the closest element in arr2.
4Step 4: Check the closest elements to see if their absolute difference with the current arr1 element is within d.
5Step 5: If no such element is found, increment the counter.
6Step 6: Return the counter as the result.

solution.py12 lines

1# Full working Python code
2import bisect
3
4def findTheDistanceValue(arr1, arr2, d):
5    arr2.sort()
6    count = 0
7    for num1 in arr1:
8        pos = bisect.bisect_left(arr2, num1)
9        if (pos < len(arr2) and abs(arr2[pos] - num1) <= d) or (pos > 0 and abs(arr2[pos - 1] - num1) <= d):
10            continue
11        count += 1
12    return count

ℹ

Complexity note: The sorting of arr2 takes O(m log m), and for each element in arr1, we perform a binary search which takes O(log m), leading to an overall complexity of O(n log n + m log m).

1Sorting arr2 allows for efficient searching of closest elements.
2Using binary search reduces the number of comparisons significantly.

Solutions and explanations are original Tejav content. Problem titles © LeetCode — use the LeetCode button above for the full problem statement.