dna.sh

dna.sh

#!/usr/bin/env bash

nucleos=(A C T G)  

print_example() {
  echo ' ex: ./dna.sh ACTG'
}

main() {
  local argv
  [[ $2 ]] && { echo 'dna: accept only one argument'; print_example; exit 0; }
  [[ $1 ]] && argv=$1 || read -p 'nucleo: ' argv
  [[ ${#1} -ne ${#nucleos[@]} ]] && { echo 'dna: accept only four chars'; print_example; exit 1; }
  argv=${argv^^}

  for ((char = 0; char < ${#argv}; char++)); do
    for nucleo in ${nucleos[@]}; do
      [[ ${argv:char:1} =~ $nucleo ]] && ((++nnucleos))
    done
  done

  [[ $nnucleos -eq ${#nucleos[@]} ]] && {
    echo ${argv} - Ok
  } || { echo 'dna: need four chars valid'; print_example; exit 1; }
}

main $@