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How to Solve Smallest K-Length Subsequence With Occurrences of a Letter Problem
Master the Smallest K-Length Subsequence With Occurrences of a Letter LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsHard#2030
LeetCode ProblemSmallest K-Length Subsequence With Occurrences of a Letter
You are given a string s, an integer k, a letter letter, and an integer repetition. Return the lexicographically smallest subsequence of s of length k that has the letter letter appear at least repetition times. The test cases are generated so that the letter appears in s at least repetition times. A subsequence is a string that can be derived from another string by deleting some or no characters without changing the order of the remaining characters. A string a is lexicographically smaller than a string b if in the first position where a and b differ, string a has a letter that appears earlier in the alphabet than the corresponding letter in b.
StringStackGreedyMonotonic Stack
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Problem Breakdown
Understanding the Smallest K-Length Subsequence With Occurrences of a Letter Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
You are given a string s, an integer k, a letter letter, and an integer repetition. Return the lexicographically smallest subsequence of s of length k that has the letter letter appear at least repetition times. The test cases are generated so that the letter appears in s at least repetition times. A subsequence is a string that can be derived from another string by deleting some or no characters without changing the order of the remaining characters. A string a is lexicographically smaller than a string b if in the first position where a and b differ, string a has a letter that appears earlier in the alphabet than the corresponding letter in b.
HardProblem #2030
LeetCodeSmallest K-Length Subsequence With Occurrences of a Letter
Related Topics
StringStackGreedyMonotonic Stack
How Phantom Code Helps
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Examples
# Example 1
Input
s = "leet", k = 3, letter = "e", repetition = 1
Output
"eet"
# Example 2
Input
s = "leetcode", k = 4, letter = "e", repetition = 2
Output
"ecde"
# Example 3
Input
s = "bb", k = 2, letter = "b", repetition = 2
Output
"bb"
Constraints
1 <= repetition <= k <= s.length <= 5 * 104
s consists of lowercase English letters.
letter is a lowercase English letter, and appears in s at least repetition times.
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Solve Smallest K-Length Subsequence With Occurrences of a Letter — You are given a string s, an integer k, a letter letter, and an integer repetiti...
Here's the optimal approach using String:
def solve(input):
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Frequently Asked Questions
Common questions about solving Smallest K-Length Subsequence With Occurrences of a Letter and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Smallest K-Length Subsequence With Occurrences of a Letter during interviews?
Phantom Code generates complete solutions instantly with proper complexity analysis, letting you focus on explaining your approach and demonstrating problem-solving skills rather than getting stuck on implementation details during high-pressure situations.
What if the interviewer asks follow-up questions or modifications to problems like Smallest K-Length Subsequence With Occurrences of a Letter?
Phantom Code adapts in real-time. Screenshot the modified problem or use audio mode to capture the interviewer's follow-up, and get an updated solution within seconds — including edge cases and optimizations.
Can Phantom Code help me communicate my solution for problems like Smallest K-Length Subsequence With Occurrences of a Letter?
Yes. Phantom Code provides step-by-step approach explanations with 3 progressive thoughts, so you can walk through your solution naturally. It also provides time and space complexity analysis to discuss trade-offs.
How does Phantom Code assist with different programming languages for Smallest K-Length Subsequence With Occurrences of a Letter type problems?
Phantom Code supports 11 programming languages including Python, Java, C++, JavaScript, TypeScript, Go, Rust, Ruby, Swift, Kotlin, and C#. Set your preferred language and get idiomatic solutions.
What coding mistakes does Phantom Code help me avoid during Smallest K-Length Subsequence With Occurrences of a Letter interviews?
Phantom Code catches common mistakes like off-by-one errors, missing edge cases, incorrect base conditions, and suboptimal approaches. It provides clean, well-structured code that handles all edge cases.
Is Phantom Code detectable when solving problems like Smallest K-Length Subsequence With Occurrences of a Letter during live interviews?
No. Phantom Code runs as an invisible desktop overlay that doesn't appear in screen shares, recordings, or proctoring software. It works with Zoom, HackerRank, CodeSignal, CoderPad, and all major platforms.
How does Phantom Code help when I'm struggling with Smallest K-Length Subsequence With Occurrences of a Letter style questions under pressure?
The AI provides structured guidance: first the approach (what algorithm/data structure to use and why), then the implementation with clean code, and finally complexity analysis. This helps you think clearly even under pressure.
Does Phantom Code work for the coding platforms used in Smallest K-Length Subsequence With Occurrences of a Letter interviews?
Yes. Phantom Code works with all major coding platforms including LeetCode, HackerRank, CodeSignal, CoderPad, HackerEarth, and any browser-based coding environment.
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