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How to Solve Number of Strings Which Can Be Rearranged to Contain Substring Problem
Master the Number of Strings Which Can Be Rearranged to Contain Substring LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
Phantom Code generates complete solutions and debugging hints that you can use while explaining your approach, so you stay calm and in control.
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Start Free for WindowsMedium#2930
LeetCode ProblemNumber of Strings Which Can Be Rearranged to Contain Substring
You are given an integer n. A string s is called good if it contains only lowercase English characters and it is possible to rearrange the characters of s such that the new string contains "leet" as a substring. For example: Return the total number of good strings of length n. Since the answer may be large, return it modulo 109 + 7. A substring is a contiguous sequence of characters within a string.
MathDynamic ProgrammingCombinatorics
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Problem Breakdown
Understanding the Number of Strings Which Can Be Rearranged to Contain Substring Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
You are given an integer n. A string s is called good if it contains only lowercase English characters and it is possible to rearrange the characters of s such that the new string contains "leet" as a substring. For example: Return the total number of good strings of length n. Since the answer may be large, return it modulo 109 + 7. A substring is a contiguous sequence of characters within a string.
MediumProblem #2930
LeetCodeNumber of Strings Which Can Be Rearranged to Contain Substring
Related Topics
MathDynamic ProgrammingCombinatorics
How Phantom Code Helps
Get real-time assistance for Number of Strings Which Can Be Rearranged to Contain Substring problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
n = 4
Output
12
# Example 2
Input
n = 10
Output
83943898
Constraints
1 <= n <= 105
How Phantom Code Helps with LeetCode Problems
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Solve Number of Strings Which Can Be Rearranged to Contain Substring — You are given an integer n. A string s is called good if it contains only lowerc...
Here's the optimal approach using Math:
def solve(input):
# Optimal O(n) solution
return result
Time: O(n) | Space: O(n)
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Undetectability and technical details
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Frequently Asked Questions
Common questions about solving Number of Strings Which Can Be Rearranged to Contain Substring and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Number of Strings Which Can Be Rearranged to Contain Substring 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 Number of Strings Which Can Be Rearranged to Contain Substring?
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 Number of Strings Which Can Be Rearranged to Contain Substring?
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 Number of Strings Which Can Be Rearranged to Contain Substring 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 Number of Strings Which Can Be Rearranged to Contain Substring 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 Number of Strings Which Can Be Rearranged to Contain Substring 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 Number of Strings Which Can Be Rearranged to Contain Substring 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 Number of Strings Which Can Be Rearranged to Contain Substring 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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