Lecture Notes on 09 Jan 2023

#  File: DNA.py

#  Description:

#  Student Name:

#  Student UT EID:

#  Partner Name:

#  Partner UT EID:

#  Course Name: CS 313E

#  Unique Number:

#  Date Created:

#  Date Last Modified:

import sys

# function to test other functions
def test_cases ():
  # test all sub_strings()
  assert all_substrings ("a") == ["a"]
  assert all_substrings ("abc") == ["abc", "ab", "bc", "a", "b", "c"]
  assert all_substrings ("") == []

  # test longest_subsequence()
  assert longest_subsequence ("a", "a") == ["a"]
  assert longest_subsequence ("abcd", "bc") == ["bc"]
  assert longest_subsequence ("abcd", "xyz") == []

  # return the result
  return "all test cases passed"
  
# Input: s a string
# Output: a list of all substrings of s
def all_substrings (s):
  # a list of all substrings of s
  result = []

  # define a window
  wnd = len(s)

  # get all substrings
  while (wnd > 0):
    idx = 0
    while (idx + wnd) <= len(s):
      sub_str = s[idx:idx+wnd]
      result.append (sub_str)
      idx += 1
    wnd = wnd - 1

  # return the result
  return result

# Input: s1 and s2 are two strings that represent strands of DNA
# Output: returns a sorted list of substrings that are the longest
#         common subsequence. The list is empty if there are no
#         common subsequences.
def longest_subsequence (s1, s2):
  return

def main():
  # test all functions
  print (test_cases())

  # read the number of pairs
  line = sys.stdin.readline()
  line = line.strip()
  num_pairs = int (line)

  # for each pair call the longest_subsequence
  for i in range (num_pairs):
    line = sys.stdin.readline()
    s1 = line.strip()
    
    line = sys.stdin.readline()
    s2 = line.strip()

    # convert the strings to upper case
    s1 = s1.upper()
    s2 = s2.upper()

    # get the longest subsequences
    result = longest_subsequence (s1, s2)

    # print the result
    if (len(result) == 0):
      print ("No Common Sequence Found")
    else:
      for item in result:
        print (item)
    
    # insert blank line
    print()

if __name__ == "__main__":
  main()