how to use values with sed in shell scripting?

i am trying te write a shell script in alphametic ,

i have 5 parameters like this

$alphametic 5790813 BEAR RARE ERE RHYME

to get

ABEHMRY -> 5790813

i tried this :

  #!/bin/bash
    echo "$2 $3 $4 $5" | sed  's/ //g ' | sed 's/./&\n/g' | sort -n |  sed '/^$/d' | uniq -i > testing
    paste -sd ''  testing  > testing2 
    sed "s|^\(.*\)$|\1 -> ${1}|" testing2 

but i get error (with the last command sed), i dont know where is the problem .

>Solution :

#!/bin/sh

val="$1"

shift

printf '%s' "$@" | awk -v FS='' -v OFS='\n' '{$1=$1}1' | sort -n | uniq | tr -d '\n'

printf " -> %s\n" "$val"

• shift removes $1 from the arguments. $@ will then contain all the arguments but the first one, and the old $2 will then be $1, $3 will be $2, etc…
• printf '%s' "$@" concatenates all the arguments into a single string
• awk -v FS='' -v OFS='\n' '{$1=$1}1' outputs each character vertically
• tr -d '\n' removes all \n characters