Learn and practice the Graphs, Tries, and Custom Data Structures patterns to solve coding interview problems.

Educative-99 in Java: Accelerate Your Coding Interview Prep

Proficiency in advanced data structures is a marker of a highly experienced engineer, and interviewers use such questions to finetune how they grade candidates. This module teaches you the use of two advanced data structures—graphs and tries—to solve relatively complex problems. To solve problems with very specific requirements that may not be handled by standard data structures, we gain experience in the advanced skill of the design, implementation, and efficient use of custom data structures.

Advanced Data Structures

# Statement
You are given an array, `routes`, representing bus routes where `routes[i]` is a bus route that the $i^{th}$ bus repeats forever. Every route contains one or more stations. You have also been given the source station, `src`, and a destination station, `dest`. Return the minimum number of buses someone must take to travel from `src` to `dest`, or return `-1` if there is no route.

**Constraints:**

* $1 \le$ `routes.length` $\le 50$
* $1 \le$ `routes[i].length` $\le 100$
* $0 \le$ `routes[i][j]` $< 1000$
* $0 \le$ `src`, `dest` $< 1000$

# Examples

Bus Routes

Statement