golang map prints out of order

Why is the map printing out of order, and how do I get it in to order?

package main

import (
	"fmt"
)

type monthsType struct {
	no   int
	text string
}

var months = map[int]string{
	1:"January", 2:"Fabruary", 3:"March", 4:"April", 5:"May", 6:"June",
	7:"July", 8:"August", 9:"September", 10:"October", 11:"Novenber", 12:"December",
}

func main(){
	for no, month := range months {
		fmt.Print(no)
		fmt.Println("-" + month)
	}
}

Prints out:

10-October
7-July
1-January
9-September
4-April
5-May
2-Fabruary
12-December
11-Novenber
6-June
8-August
3-March

Code:

func DemoSortMap() (int, error) {
    fmt.Println("use an array to access items by number:")
    am := [2]string{"jan", "feb"}
    for i, n := range am {
        fmt.Printf("%2d: %s\n", i, n)
    }
    fmt.Println("maps are non-sorted:")
    mm := map[int]string{2: "feb", 1: "jan"}
    for i, n := range mm {
        fmt.Printf("%2d: %s\n", i, n)
    }
    fmt.Println("access items via sorted list of keys::")
    si := make([]int, 0, len(mm))
    for i := range mm {
        si = append(si, i)
    }
    sort.Ints(si)
    for _, i := range si {
        fmt.Printf("%2d: %s\n", i, mm[i])
    }
    
    return 0, nil
}

(most of it stolen from M. Summerfield's book)

output:

use an array to access items by number:
 0: jan
 1: feb
maps are non-sorted:
 2: feb
 1: jan
access items via sorted list of keys::
 1: jan
 2: feb

Maps are not sorted so you may use a slice to sort your map. Mark Summerfield's book "Programming in Go" explains this on page 204 and is highly recommended.

This is very late answer, but from what I have read maps are unsorted by design, and are random as one should not rely on the order.

Besides using the sort package together with a second map, one can also use the fmt.Prinln(theMap), which will print the map sorted.

>fmt: print maps in key-sorted order

This will print the map typically as follows:

map[key:value
key:value
key:value
]

But this might not be what you want...

By using the fmt.Sprint one can then manipulate the string if needed.

i.e.

s := fmt.Sprint(theMap)
s1 := s[4 : len(s)-1] // remove map[ and ]
fmt.Println(s1)