How to sort a map by keys or values in Go?

To sort a map by keys or values in Go, you can follow the steps below:

Import the necessary packages:

import (
    "fmt"
    "sort"
)

Define a map with the desired key-value pairs.

myMap := map[string]int{
    "banana": 2,
    "apple":  1,
    "kiwi":   3,
}

To sort the map by keys, create a slice of keys and use the sort.Strings() function to sort the keys.

var sortedKeys []string
for key := range myMap {
    sortedKeys = append(sortedKeys, key)
}
sort.Strings(sortedKeys)

To sort the map by values, create a slice of key-value pairs and use the sort.Slice() function to sort the slice based on the values using a custom comparison function.

var sortedPairs []struct {
    Key   string
    Value int
}
for key, val := range myMap {
    sortedPairs = append(sortedPairs, struct {
        Key   string
        Value int
    }{key, val})
}
sort.Slice(sortedPairs, func(i, j int) bool {
    return sortedPairs[i].Value < sortedPairs[j].Value
})

Finally, iterate over the sorted keys or pairs and access the values from the original map.

fmt.Println("Sorted by keys:")
for _, key := range sortedKeys {
    fmt.Println(key, myMap[key])
}

fmt.Println("Sorted by values:")
for _, pair := range sortedPairs {
    fmt.Println(pair.Key, pair.Value)
}

This will print the map sorted by keys first and then by values.

Make sure to remember that maps in Go are inherently unordered, so sorting a map doesn't change the original map but rather creates a sorted representation of its contents.