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This is a hard difficulty Coding & Algorithms question, commonly asked during Technical Screen rounds at Databricks.

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This question is commonly asked for Software Engineer candidates at Databricks during technical interviews.

Minimize run-length encoded length with deletions

Quick Overview

This question evaluates proficiency in string manipulation, run-length encoding concepts, and dynamic programming-based optimization under deletion constraints.

hard
Databricks
Coding & Algorithms
Software Engineer

Minimize run-length encoded length with deletions

Company: Databricks

Role: Software Engineer

Category: Coding & Algorithms

Difficulty: hard

Interview Round: Technical Screen

### Problem You are given a string `s` (uppercase English letters) and an integer `k`. You may delete **at most `k` characters** from `s`. After deletions, you compress the resulting string using **run-length encoding (RLE)**: - Consecutive equal characters are replaced by the character followed by the run length **only if the run length > 1**. - Examples: - `"A" -> "A"` - `"AA" -> "A2"` - `"AAA" -> "A3"` - `"AABCCC" -> "A2BC3"` ### Task Return the **minimum possible length** of the RLE-compressed string after deleting at most `k` characters. ### Input / Output - Input: string `s`, integer `k` - Output: integer (minimum compressed length) ### Constraints (typical interview bounds) - `1 <= len(s) <= 100` - `0 <= k <= len(s)` ### Clarifications - The “length” is the number of characters in the encoded string (e.g., `"A12"` has length 3).

Quick Answer: This question evaluates proficiency in string manipulation, run-length encoding concepts, and dynamic programming-based optimization under deletion constraints.

You are given a string s consisting of uppercase English letters and an integer k. You may delete at most k characters from s. After deletions, compress the remaining string using run-length encoding (RLE): each maximal block of consecutive equal characters becomes the character followed by its count only when the count is greater than 1. For example, A becomes A, AA becomes A2, and AABCCC becomes A2BC3. Return the minimum possible length of the compressed string. If all characters are deleted, the compressed length is 0.

Constraints

1 <= len(s) <= 100
0 <= k <= len(s)
s consists only of uppercase English letters

Examples

Input: ('AAABCCCD', 2)

Expected Output: 4

Explanation: Delete B and D to get AAACCC, which compresses to A3C3 with length 4.

Input: ('AABBA', 2)

Expected Output: 2

Explanation: Delete both B characters to get AAA, which compresses to A3 with length 2.

Input: ('A', 0)

Expected Output: 1

Explanation: No deletions are allowed. A compresses to A, so the length is 1.

Input: ('ABCDE', 5)

Expected Output: 0

Explanation: You may delete all characters, leaving an empty string with compressed length 0.

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Quick Overview

Minimize run-length encoded length with deletions

Constraints

Examples

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