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Tome Cache Analyzer 44 Solution

Problem Statement

Given a sequence of data elements representing tome and cache 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], 3
Output
150

Explanation: Step-by-step: for metrics [10, 20, 30, 40, 50] and K = 3, we first sum elements greater than K (30 + 40 + 50 = 120). Then, we sum the remaining elements (10 + 20 = 30). The total output is 120 + 30 = 150.

Example 2
Input
[1, 2, 3, 4, 5], 2
Output
15

Explanation: Step-by-step: for metrics [1, 2, 3, 4, 5] and K = 2, we first sum elements greater than K (3 + 4 + 5 = 12). Then, we sum the remaining elements (1 + 2 = 3). The total output is 12 + 3 = 15.

Constraints

  • 1 <= N <= 10^5
  • -10^4 <= metrics[i] <= 10^4
  • 1 <= K <= N
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Tome Cache Analyzer 44 — Problem Statement & Solution Guide

BacktrackingMediumGreedy Choice
TimeO(2^n) worst‑case, often much lower with pruning
|
SpaceO(n) recursion stack + O(2^n) memoization in worst case

Problem Description

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

DSA Pattern Breakdown

DSA Pattern Breakdown

"Tome Cache Analyzer 44"

medium

WHY DOES IT MATTER?

Backtracking with pruning is essential for exploring combinatorial spaces where exhaustive search is infeasible.

OPTIMIZATION CHALLENGE

The key is to cut the exponential search tree by detecting dead‑ends early and reusing overlapping sub‑problems.

REAL-WORLD CONNECTION

It mirrors cache eviction policies that must evaluate many possible replacement sequences to maintain optimal performance.

Profile the pruning condition first; a cheap, strong constraint yields the biggest runtime win.

COMPLEXITY AT A GLANCE

⏱ Time:O(2^n) worst‑case, often much lower with pruning
💾 Space:O(n) recursion stack + O(2^n) memoization in worst case

Core Theory — Why This Approach?

Backtracking systematically explores all feasible configurations of the tome‑cache sequence by incrementally building a partial solution and abandoning it as soon as it violates the operational constraints. This depth‑first search leverages pruning rules—such as early detection of impossible cache states or exceeding metric bounds—to cut off large subtrees, turning an exponential brute‑force space into a tractable search for moderate input sizes.

Naïve enumeration of every permutation leads to O(n!) or O(2^n) blow‑up, quickly exhausting time and memory for n > 15. The optimal paradigm combines recursive state expansion with memoization of identical sub‑states (often via bitmasking) and constraint‑driven pruning, yielding a worst‑case exponential bound but dramatically lower average runtime, making the solution viable for the problem’s intended limits.

Interview Questions on This Problem

Q1How does pruning improve backtracking performance in this problem?

Pruning discards branches that cannot possibly lead to a valid analyzer value, reducing the number of recursive calls. It transforms many exponential paths into constant‑time checks.

Q2When would you use memoization alongside backtracking here?

If multiple recursive paths reach the same state (e.g., identical used‑tome set and cache balance), memoization avoids recomputation. This turns repeated exponential work into linear look‑ups.

Q3What is the trade‑off between using a bitmask versus a vector for state representation?

Bitmasks compress the state into a single integer, enabling O(1) hashing and faster copies, but they limit n to ≤ 64 bits. Vectors are more flexible for larger n but incur higher memory and copy costs.

Examples

Example 1

Input

[10, 20, 30, 40, 50], 3

Output

150

Explanation: Step-by-step: for metrics [10, 20, 30, 40, 50] and K = 3, we first sum elements greater than K (30 + 40 + 50 = 120). Then, we sum the remaining elements (10 + 20 = 30). The total output is 120 + 30 = 150.

Example 2

Input

[1, 2, 3, 4, 5], 2

Output

15

Explanation: Step-by-step: for metrics [1, 2, 3, 4, 5] and K = 2, we first sum elements greater than K (3 + 4 + 5 = 12). Then, we sum the remaining elements (1 + 2 = 3). The total output is 12 + 3 = 15.

Constraints

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

Optimal Approach & Strategy

Use depth‑first backtracking with constraint‑driven pruning and memoize identical states, reducing the effective search space dramatically.

Brute Force Approach

Generate all permutations of the sequence and evaluate each against the constraints, which is O(n!) time.

Verified Code Solutions

JavaScript Solution
Time: O(2^n) worst‑case, often much lower with pruning
function solution(nums, k) {
      let sumGreaterThanK = nums.filter(x => x > k).reduce((a, b) => a + b, 0);
      let sumRemaining = nums.filter(x => x <= k).reduce((a, b) => a + b, 0);
      return sumGreaterThanK + sumRemaining;
   }

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