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Vault Registry Analyzer 29 Solution

Problem Statement

Given a sequence of data elements representing vault and registry metrics, construct an optimal algorithm to evaluate and compute the target analyzer value under given operational constraints.

Example 1
Input
[10, 20, 30, 40, 50, 60, 70, 80, 90]
Output
40

Explanation: Step-by-step: Given an array of vault and registry metrics, we perform a binary search to find the smallest metric greater than K. If K is equal to the metric at the mid index, we continue the search on the right half of the array. If the input array is empty, we return -1 as there are no metrics to search from.

Example 2
Input
[5, 15, 25, 35, 45, 55, 65, 75, 85, 95]
Output
35

Explanation: Step-by-step: Given an array of vault and registry metrics, we perform a binary search to find the smallest metric greater than K. If K is equal to the metric at the mid index, we continue the search on the right half of the array. If the input array is empty, we return -1 as there are no metrics to search from.

Constraints

  • 1 <= N <= 10^5
  • -10^4 <= metrics[i] <= 10^4
  • 1 <= K <= N
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Vault Registry Analyzer 29 — Problem Statement & Solution Guide

Binary SearchHardBitmasking
TimeO(log n)
|
SpaceO(1)

Problem Description

Given a sequence of data elements representing vault and registry metrics, construct an optimal algorithm to evaluate and compute the target analyzer value under given operational constraints.

DSA Pattern Breakdown

DSA Pattern Breakdown

"Vault Registry Analyzer 29"

hard

WHY DOES IT MATTER?

Binary search reduces search complexity from linear to logarithmic, a game‑changer for massive datasets.

OPTIMIZATION CHALLENGE

The key is to shrink the candidate interval by half each iteration, turning O(n) work into O(log n).

REAL-WORLD CONNECTION

Databases use B‑tree indexes, which are essentially multi‑level binary searches for fast record retrieval.

Always guard against off‑by‑one errors and overflow; write the loop as while (low <= high) and update bounds carefully.

COMPLEXITY AT A GLANCE

⏱ Time:O(log n)
đź’ľ Space:O(1)

Core Theory — Why This Approach?

Binary search exploits the monotonic property of sorted data to halve the search space at each step, guaranteeing logarithmic time. In the Vault Registry Analyzer, the metrics are pre‑ordered by timestamp or identifier, allowing us to compare the target analyzer value against the middle element and discard half of the array recursively. Naïve linear scans examine every element, leading to O(n) time which becomes prohibitive when n reaches millions, especially under tight latency SLAs. The optimal paradigm combines binary search with careful handling of duplicate boundaries and overflow‑safe mid calculations, ensuring O(log n) time while using only O(1) extra space.

Interview Questions on This Problem

Q1Why does binary search require the input array to be sorted?

Because it relies on the ordering to decide which half can be discarded after each comparison. Without sorting, the decision would be invalid and correctness breaks.

Q2How can you prevent integer overflow when computing the middle index?

Use mid = low + (high - low) / 2 instead of (low + high) / 2. This keeps the addition within the range of the integer type.

Q3What modification is needed to find the first occurrence of a target in a list with duplicates?

After a match, continue searching the left half (high = mid - 1) while recording the index. The final recorded index is the leftmost occurrence.

Examples

Example 1

Input

[10, 20, 30, 40, 50, 60, 70, 80, 90]

Output

40

Explanation: Step-by-step: Given an array of vault and registry metrics, we perform a binary search to find the smallest metric greater than K. If K is equal to the metric at the mid index, we continue the search on the right half of the array. If the input array is empty, we return -1 as there are no metrics to search from.

Example 2

Input

[5, 15, 25, 35, 45, 55, 65, 75, 85, 95]

Output

35

Explanation: Step-by-step: Given an array of vault and registry metrics, we perform a binary search to find the smallest metric greater than K. If K is equal to the metric at the mid index, we continue the search on the right half of the array. If the input array is empty, we return -1 as there are no metrics to search from.

Constraints

  • 1 <= N <= 10^5
  • -10^4 <= metrics[i] <= 10^4
  • 1 <= K <= N

Optimal Approach & Strategy

Apply binary search on the sorted metrics, adjusting low/high pointers based on comparisons to achieve O(log n) time.

Brute Force Approach

Iterate through the entire array checking each element until the target is found, which costs O(n) time.

Verified Code Solutions

JavaScript Solution
Time: O(log n)
function solution(nums, K) {
   if (nums.length === 0) return -1;
   let left = 0, right = nums.length - 1;
   while (left <= right) {
       let mid = Math.floor((left + right) / 2);
       if (nums[mid] > K) {
           if (mid === 0 || nums[mid - 1] <= K) return nums[mid];
           right = mid - 1;
       } else {
           left = mid + 1;
       }
   }
   return -1;
}

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