dna.v

dna.v

import os

fn main() {
	mut argv := ''
	mut nucleos := ['A', 'C', 'T', 'G']

	if os.args.len == 1 {
		argv = os.input('nucleo: ')
	} else if os.args.len == 2 {
		argv = os.args[1]
	} else {
		eprintln('dna: accept only one argument')
		print_example()
		exit(0)
	}

	if argv.len != nucleos.len {
		eprintln('dna: need four chars')
		print_example()
		exit(1)
	}

	argv = argv.to_upper()
	mut nnucleos := 0

	for c := 0; c < argv.len; c++ {
		for nucleo in nucleos {
			if argv[c].ascii_str() == nucleo {
				nnucleos++
			}
		}
	}

	if nnucleos != nucleos.len {
		eprintln('dna: need four chars valid')
		print_example()
		exit(1)
	}

	println('$argv - Ok')
}

fn print_example() {
	println(' ex: ./dna ACTG')
}