Question

I’m trying to create a program that can analyze a string sequence. Currently, my program is capable of examining the sequence character by character, but I don’t know how to cleanly get it to recognize the end of the string, which will be variable.

str_exp="ABCDAABKLYWAKAT"

n=0
x=5

while n<=10:

  window=str_exp[n:x]
  print window,
  n+=1
  x+=1

  countA=window.count('A') 
  print countA

This should output:

ABCDA 2
BCDAA 2
CDAAB 2
DAABK 2
AABKL 2
ABKLY 1
BKLYW 0
KLYWA 1
LYWAK 1
YWAKA 2
WAKAT 2

Answer 1

You just need to change the condition on your while loop to be based on len(str_exp), which will detect the length of the string. I’ll leave it up to you to figure out the arithmetic, because you’ve got all the basic pieces