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Java Java Data Structures - Retired Efficiency! Implement Chooser UI

Gaurang Kotasthane
Gaurang Kotasthane
1,394 Points
Posted by Gaurang Kotasthane
Gaurang Kotasthane
1,394 Points

return choice -1

I did not understand why we returned choice as -1 any help would be appreciated thanks

1 Answer

Matthias Margot
Matthias Margot
7,236 Points
Matthias Margot
Matthias Margot
7,236 Points

You know how in the console user interface the artists and songs to choose from are ordered from 1 to (total number of artists)? This is starting at '1' problem is indices (plural of index) in coding start at 0. So if you choose the seconds artist your choice is '2' but the index of the artist in the ArrayList (or whatever collection you're using, been a while since i watched that video, might be a map don't remember) is actually not '2' but 2 - 1 which is '1'. The second entry in your list has the index '1' because the first entry has the index '0' so that's why you take 1 away from choice.