How to Solve Number of Ways to Divide a Long Corridor Problem
Master the Number of Ways to Divide a Long Corridor LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
Interview Coder generates complete solutions and debugging hints that you can use while explaining your approach, so you stay calm and in control.
Number of Ways to Divide a Long Corridor
Along a long library corridor, there is a line of seats and decorative plants. You are given a 0-indexed string corridor of length n consisting of letters 'S' and 'P' where each 'S' represents a seat ...
Interview Coder will help you solve this problem in real-time during your interview
✨ Get instant solutions, explanations, and code generation
Understanding the Number of Ways to Divide a Long Corridor Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
Along a long library corridor, there is a line of seats and decorative plants. You are given a 0-indexed string corridor of length n consisting of letters 'S' and 'P' where each 'S' represents a seat and each 'P' represents a plant. One room divider has already been installed to the left of index 0, and another to the right of index n - 1. Additional room dividers can be installed. For each position between indices i - 1 and i (1 <= i <= n - 1), at most one divider can be installed. Divide the corridor into non-overlapping sections, where each section has exactly two seats with any number of plants. There may be multiple ways to perform the division. Two ways are different if there is a position with a room divider installed in the first way but not in the second way. Return the number of ways to divide the corridor. Since the answer may be very large, return it modulo 109 + 7. If there is no way, return 0.
Number of Ways to Divide a Long Corridor
Related Topics
How Interview Coder Helps
Get real-time assistance for Number of Ways to Divide a Long Corridor problems during coding interviews. Interview Coder provides instant solutions and explanations.
Examples
corridor = "SSPPSPS"
3
There are 3 different ways to divide the corridor. The black bars in the above image indicate the two room dividers already installed. Note that in each of the ways, each section has exactly two seats.
corridor = "PPSPSP"
1
There is only 1 way to divide the corridor, by not installing any additional dividers. Installing any would create some section that does not have exactly two seats.
corridor = "S"
0
There is no way to divide the corridor because there will always be a section that does not have exactly two seats.
Constraints
n == corridor.length
1 <= n <= 105
corridor[i] is either 'S' or 'P'.
How Interview Coder Helps with Leetcode Problems
Trust anchors reduce friction for conversion. Reinforce undetectability claims, platform compatibility, user counts, and the free trial to remove perceived risk.
See Interview Coder in Action
Watch how Interview Coder helps solve LeetCode problems during live interviews
Undetectability Checklist
Platform Compatibility
User results and traction
More than 87,000 developers use Interview Coder and early launch metrics showed rapid adoption. Social proof signals that this approach helps real candidates land offers across a range of companies.
Undetectability and technical details
Our native desktop architecture avoids common detection vectors used by browser extensions. We provide a clear checklist so you can run basic checks and confirm the app will be invisible during live interviews.
Platform compatibility and limitations
We work with Zoom, HackerRank, CodeSignal, CoderPad and other web based platforms, with a known list of app version caveats. Check the compatibility note and request a browser link if a specific desktop app is unsupported.
Frequently Asked Questions
Common questions about solving Number of Ways to Divide a Long Corridor and using Interview Coder during coding interviews.
Interview Coder 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.
Ready to Get Started?
Download Interview Coder now and join thousands of developers who have aced their coding interviews