A simple python program to count nuclotides in a dna strand.

dna.py

"""
A string is simply an ordered collection of symbols selected from some alphabet and formed into a word; the length of a string is the number of symbols that it contains.

An example of a length 21 DNA string (whose alphabet contains the symbols 'A', 'C', 'G', and 'T') is "ATGCTTCAGAAAGGTCTTACG."

Given: A DNA string s of length at most 1000 nt.

Return: Four integers (separated by spaces) counting the respective number of times that the symbols 'A', 'C', 'G', and 'T' occur in s.
"""

import os

imput_filepath = '/tmp/rosalind_dna.txt'

try:
    with open(imput_filepath) as line:
        dna = line.readline()

    print(str(dna.count('A')) + ' ' + str(dna.count('C')) + ' ' + str(dna.count('G')) + ' ' + str(dna.count('T'))) 
   
except IOError as err:
    print('File Error : ' + str(err))