How to sort a slice of ints in Golang?
In Go, slices provide a flexible way to manage sequences of elements. To sort a slice of ints, the sort package offers a few straightforward functions. In this article we will learn How to Sort a Slice of Ints in Golang.
Example
package main
import (
"fmt"
"sort"
)
func main() {
intSlice := []int{42, 23, 16, 15, 8, 4}
fmt.Println("Before:", intSlice)
// Sorting in ascending order
sort.Ints(intSlice)
fmt.Println("After:", intSlice)
}
Output
Before: [42 23 16 15 8 4] After: [4 8 15 16 23 42]
Syntax
func Ints(slc []int) #Sorting with sort.Ints
func IntsAreSorted(slc []int) bool # Check Slice sorting with sort.IntsAreSorted
Table of Content
Sorting with sort.Ints
The sort.Ints function sorts a slice of ints in ascending order, modifying the slice directly.
Syntax
func Ints(slc []int)Example
Using the earlier intSlice example, we applied sort.Ints to sort the integers in place. The result is an ascending order.
Checking if a Slice is Sorted with sort.IntsAreSorted
If you need to check whether a slice is already sorted in ascending order, you can use sort.IntsAreSorted. This function returns true if the slice is sorted and false otherwise.
Syntax
func IntsAreSorted(slc []int) boolExample
package main
import (
"fmt"
"sort"
)
func main() {
intSlice := []int{42, 23, 16, 15, 8, 4}
// Check if the slice is sorted
fmt.Println("sorted before sorting?:", sort.IntsAreSorted(intSlice))
// Sort the slice
sort.Ints(intSlice)
// Check again
fmt.Println("sorted after sorting?:", sort.IntsAreSorted(intSlice))
}
Output
sorted before sorting?: false sorted after sorting?: true
Sorting in Descending Order with sort.Slice
If you want to sort in descending order, you can use sort.Slice with a custom comparison function.
Example
package main
import (
"fmt"
"sort"
)
func main() {
intSlice := []int{42, 23, 16, 15, 8, 4}
// Sort in descending order
sort.Slice(intSlice, func(i, j int) bool {
return intSlice[i] > intSlice[j]
})
fmt.Println("descending order:", intSlice)
}
Note: If you are encountering an error indicating that the
sort.Slicefunction is not recognized, it may be due to using an older version of Go that does not support this function. Thesort.Slicefunction was introduced in Go 1.8, so ensure that your Go version is at least 1.8 or higher.
