Round 1: Data Structures & Problem Solving

Question : Return the shortest distance from A -> F
Input : {"5","A","B","C","D","F","A-B","A-C","B-C","C-D","D-F"}
Ouput : Shortest path from A to F: A -> C -> D -> F

I haven't practiced shortest distance problems, so I wasn't able to explain the correct approach for this one.