Find Max and Min of Double Linked List in Golang - list

Question

I need to find a function where I get the max and min value (using int values) of a Double Linked List (not an array) using Golang. I've write the code for getting this values for array but i have no idea where to start when i use a double linked list (or circular) :
package main
import "fmt"
func main() {
var a = [5]int{11, -4, 7, 8, -10}
min, max := findMinAndMax(a)
fmt.Println("Min: ", min)
fmt.Println("Max: ", max)
}
This works but i need to replace the array with a double list (for ex. called 'l') where i have 5 int values (2,5,7,9,12) and i need to get the max and min values
l={2,5,7,9,12} // Created a double linked list

Answer 1

Below code will help you to find the answer. I used Go container/list package's (double) list to findMinAndMax operation.
package main
import (
"container/list"
"fmt"
)
func main() {
var a = [5]int{11, -4, 7, 8, -10}
//declare a double list
i := list.New()
// push a's values to list
for _, valueA := range a {
i.PushFront(valueA)
}
min, max := findMinAndMax(i)
fmt.Println("Min: ", min) //Output: Min: -10
fmt.Println("Max: ", max) //Output: Max: 11
}
func findMinAndMax(a *list.List) (min int, max int) {
min = a.Front().Value.(int)
max = a.Front().Value.(int)
for e := a.Front(); e != nil; e = e.Next() {
value := e.Value.(int)
if value < min {
min = value
}
if value > max {
max = value
}
}
return min, max
}
The Go Playground for list
For circular linked list (ring) implementation will be as below. I used Go container/ring package's Ring for the implementation.
package main
import (
"container/ring"
"fmt"
)
func main() {
var a = [5]int{11, -4, 7, 8, -10}
//declare a container ring
r := ring.New(len(a))
// push a's values to ring
for _, valueA := range a {
r.Value = valueA
r = r.Next()
}
min, max := findMinAndMax(r)
fmt.Println("Min: ", min) //Output: Min: -10
fmt.Println("Max: ", max) //Output: Max: 11
}
func findMinAndMax(r *ring.Ring) (min int, max int) {
min = r.Value.(int)
max = r.Value.(int)
tmp := r
for {
value := r.Value.(int)
if value < min {
min = value
}
if value > max {
max = value
}
r = r.Next()
// r = tmp means one ring circle is completed
if r == tmp {
break
}
}
return min, max
}
The Go Playground for ring

Answer 2

This was the code i've done for getting max and min of an arrau but i need both from a double linked list, hope this is understood:
func findMinAndMax(a [5]int) (min int, max int) {
min = a[0]
max = a[0]
for _, value := range a {
if value < min {
min = value
}
if value > max {
max = value
}
}
return min, max
}