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Python

Angelique Pat
Angelique Pat
1,996 Points
Posted by Angelique Pat
Angelique Pat
1,996 Points

Why do we need to do [keeper -1] to get the goal keeper's name?

Partial code:

keeper = input("Please select the goal keeper by selecting the player number . (1-{})".format(len(players)))

keeper = int(keeper)

print("Great!! The goalkeeper for the game will be {}.".format(players[keeper-1]))

Jonathan Jimenez
seal-mask
.a{fill-rule:evenodd;}techdegree
Jonathan Jimenez
Python Development Techdegree Student 1,970 Points
Jonathan Jimenez
.a{fill-rule:evenodd;}techdegree
Jonathan Jimenez
Python Development Techdegree Student 1,970 Points

One of the reason is to keep your code simple and short following the idea of DRY ( Don't Repeat Yourself) As well it will select the last index (player) inside the keeper list

1 Answer

Jeff Muday
MOD
Jeff Muday
Treehouse Moderator 28,720 Points
Jeff Muday
Jeff Muday
Treehouse Moderator 28,720 Points

Since Python (and most other modern languages) have 0 based arrays/lists, the first player's index would be zero. So if you wanted the first player it is stored in players[0]. By the way, you're going to see this quite a bit if you program in Python and Javascript!

Most people if presented with a user interface and want the first player, they will type in the number 1. We have to compensate for the zero based array and do the subtraction for them!

Hope this makes sense for you.