docs(revconcatalternate): fix subject

- format exercise title
- upgrade instructions
- add missing import 'piscine'
- fix white-spaces
- fix output

subjects/revconcatalternate/README.md

@@ -1,44 +1,44 @@
-## reverseconcatalternate
+## revconcatalternate
 
 ### Instructions
 
-Write a function that receives two slices of int as arguments and returns a new one with the result of alternating the values of each in reverse order.
-- The input slices may be of different lengths.
+Write a function `RevConcatAlternate()` that receives two slices of `int` as arguments and returns a new slice with alternated values of each slice in reverse order.
+- The input slices can have different lengths.
 - The new slice should contain the elements of the larger slice first and then the elements of the smaller slice.
 - If the slices are of equal length, the new slice should contain the elements of the first slice first and then the elements of the second slice.
-- The new slice should be in the reverse order of the input slices.
 
 ### Expected function
 
 ```go
 func RevConcatAlternate(slice1,slice2 []int) []int {
-    
+
 }
 ```
 
 ### Usage
 
-Here is a possible program to test your function :
+Here is a possible program to test your function:
 
 ```go
 package main
 
 import (
 	"fmt"
+	"piscine"
 )
 
 func main() {
-	fmt.Println(RevConcatAlternate([]int{1,2,3},[]int{4,5,6}))
-	fmt.Println(RevConcatAlternate([]int{1,2,3},[]int{4,5,6,7,8,9}))
-	fmt.Println(RevConcatAlternate([]int{1,2,3},[]int{}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{4, 5, 6, 7, 8, 9}))
+	fmt.Println(piscine.RevConcatAlternate([]int{1, 2, 3}, []int{}))
 }
 ```
 
-And its output :
+And its output:
 
 ```console
 $ go run .
-[3,6,2,5,1,4]
-[9,1,8,2,7,3,6,5,4]
-[3,2,1]
+[3 6 2 5 1 4]
+[9 3 8 2 7 1 6 5 4]
+[3 2 1]
 ```