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In Go, there are two ways to create a map. We’ll be covering both in this exercise.

Creating a map with make

We can use the make function to create an empty map. The format is:

variableName := make(map[keyType]valueType)

For example, we could create an empty map of product name to price:

prices := make(map[string]float32)

Creating empty maps is useful when we don’t know what the content of our map will be. But sometimes the content of the map is known ahead of time.

Creating a map with values

If we know some map values, we can specify them as follows:

variableName := map[keyType]valueType{
    name1: value1,
    name2: value2,
    name3: value3,
}

For example, we can create a contact list with:

contacts := map[string]int{
    "Joe":    2126778723,
    "Angela": 4089978763,
    "Shawn":  3143776876,
    "Terell": 5026754531,
}

We’ve learned how to create our maps, but how do we access the elements within them? We’ll do that in the next exercise. Before that, let’s practice creating some maps!

Instructions

Let’s create some code to run a donut shop.

Use the make syntax to create a map named orders with a string key type and float32 value type. We can use orders to keep track of how much our customers are spending.

Then use the fmt.Println function to print out your empty map of orders.

We need to keep track of our donut inventory!

Create a map donuts with a key type of string and a value of int. Use the following table for the map’s values:

Kind	Count
frosted	10
chocolate	15
jelly	8

Then, use the fmt.Println function to print out your map of donut inventory.

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