How to Solve Keys and Rooms Problem
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Keys and Rooms
There are n rooms labeled from 0 to n - 1 and all the rooms are locked except for room 0. Your goal is to visit all the rooms. However, you cannot enter a locked room without having its key. When you ...
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Understanding the Keys and Rooms Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
There are n rooms labeled from 0 to n - 1 and all the rooms are locked except for room 0. Your goal is to visit all the rooms. However, you cannot enter a locked room without having its key. When you visit a room, you may find a set of distinct keys in it. Each key has a number on it, denoting which room it unlocks, and you can take all of them with you to unlock the other rooms. Given an array rooms where rooms[i] is the set of keys that you can obtain if you visited room i, return true if you can visit all the rooms, or false otherwise.
Keys and Rooms
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How Interview Coder Helps
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Examples
rooms = [[1],[2],[3],[]]trueWe visit room 0 and pick up key 1. We then visit room 1 and pick up key 2. We then visit room 2 and pick up key 3. We then visit room 3. Since we were able to visit every room, we return true.
rooms = [[1,3],[3,0,1],[2],[0]]falseWe can not enter room number 2 since the only key that unlocks it is in that room.
Constraints
n == rooms.length2 <= n <= 10000 <= rooms[i].length <= 10001 <= sum(rooms[i].length) <= 30000 <= rooms[i][j] < nAll the values of rooms[i] are unique.How Interview Coder Helps with Leetcode Problems
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Frequently Asked Questions
Common questions about solving Keys and Rooms and using Interview Coder during coding interviews.
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