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Scala provides us with a wide array
of built in, higher order functions.

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Most of the time, we'll make use
of these built in functions.

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However, there may be times where we want
to create our own higher order function.

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Let's take a look at how to do that.

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In an earlier video,
we created a map which holds the name and

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ranking of our avengers.

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Let's create a higher order function
which takes three avengers and

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compares their ranking by
finding the men and the mask.

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Let's copy the avengers map
we have created earlier.

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Now let's take out the rankings from
these and store them into variables.

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Awesome.

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Now we have the three rankings.

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Let's use them in our function.

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Great.

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We've created a function called compare,

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which takes three arguments that are
integers and has a function noted by f:

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that takes these three arguments and
combines them to one.

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There are several ways we
can invoke such a function.

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Passing the values of the rankings for

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each Avenger, along with the function we
would like to use to compare the three.

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First, let's get an idea of which one
of our avengers has the best ranking.

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In this example,

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we're comparing the three arguments passed
in by finding the minimum between them.

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Remember our compare function
takes a function parameter

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which accepts a three arguments.

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The function we pass to compare is the min
function with underscores as wildcards

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which represent avenger1,
avenger2 and avenger3.

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Let's recompile our code and
check out our results.

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As expected,

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we get eight as a result, which is
the minimum ranking between our Avengers.

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A ranking of eight belongs
to Captain America.

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Captain America is our best ranked
Avenger, as his value is closest to one.

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Similarly, we can pass another function
and find out the worst ranked Avenger.

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In this case,

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we compared the three arguments passed
by finding the maximum between them.

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Remember, our compare function
takes a function parameter

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which accepts three arguments.

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The function we passed to compare is
the max function with underscores as

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wildcards which represent avenger one,
avenger two, and avenger three.

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Let's check out the results.

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Awesome, as expected we got the ranking
that's furthest away from one between our

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three avengers.

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Cool.

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Not only did we learn about how to
use higher-order functions, but

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we also learned how to create our own.

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In the next video,
we'll discuss another topic, closures.

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See you there.