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In this exercise,

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you are going to write a program

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that is going to select a random name from a list of names.

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And the person selected will have to pay

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for everyone's food bill.

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This might be handy when you're going out for dinner

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with your friends, or maybe when you're going out

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with your colleagues and you want to keep things simple.

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So this is a Banker Roulette and the idea

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is we're going to put a bunch of names

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into the Input area,

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and these names will be separated by a comma and a space.

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This is very important.

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On line one, we've got some code that is going

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to do some pre-processing.

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It's going to take the input and it's going to split

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that string by a comma and a space.

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And then it's going to add each of those names into a list,

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which you can then access in that name's variable.

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Now don't worry about getting hold of the Input,

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we've already sorted that out behind the scenes for you,

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all you have to do is given a list of names,

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how can you pick out a random one from those names

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and then print out that name and then the phrase,

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"is going to buy the meal today."

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So take a look inside the Example Input

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and Example Output and figure out how you

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can get this to work.

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Once you're done, hit Submit and then test your code

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against our pre-formatted test cases.

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Now remember, your output can only have one line,

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and it must match the format written in the example output.

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All right, let's work through the solution together.

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The first thing we're going to do is to get hold

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of the total number of items in the list.

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So we're creating a variable called num_items,

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and we're using the len() function in Python to calculate

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how many items there are in our list,

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that is the list of names.

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Next, we are taking the number of items,

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we're subtracting it by 1

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because remember, lists start from 0

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and then to the last index.

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So if a list had three items,

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then it would be at positions 0, 1, and 2.

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So that's why we're subtracting number_items by 1.

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And then we're using random.randint()

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in order to get a random number between 0

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and the last index.

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And then that is going to be the number

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we're going use to pick out a random name in the next step.

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Once we've got our random number,

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then it's as simple as taking our list of names,

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putting a square bracket [ ] afterwards

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and then putting our random choice,

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that random number into the square brackets

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to pick out a random name.

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And finally, we put that name into our print statement

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and print out that person is going to buy the meal today.