Dhvani Shah Dhvani Shah - 3 months ago 7
Python Question

to convert a MCQ in the required format - python

I am trying to convert MCQ which is as follows:

Which will legally declare, construct, and initialize an array?
A. int [] myList = {"1", "2", "3"};
B. int [] myList = (5, 8, 2);
C. int myList [] [] = {4,9,7,0};
D. int myList [] = {4, 3, 7};
ANSWER: D


into the required format which is as mentioned below:

Which will legally declare, construct, and initialize an array?
int [] myList = {"1", "2", "3"};
int [] myList = (5, 8, 2);
int myList [] [] = {4,9,7,0};
*int myList [] = {4, 3, 7};


The logic I'm trying is as follows:

1. Open the text file and trying to fetch the line number of "ANSWER: D"
2. Open the file again and go to that line number
3. write a for loop which will iterate max 5 times till it find the match
"D." is found.
4.Once the match is found replace it with '*'


Below is the code I tried:

import re

ans = []
line_no = []

class Options:
def __init__(self, ans1, num1):
self.a = ans1
self.n = num1
#print(self.a, self.n)


pattern = 'ANSWER: [A-Z]' # to fetch the answer of each question
r = re.compile(pattern)

pattern1 = '[A-F]\.\s'
re1 = re.compile(pattern1)



with open (r"C:\Users\dhvani\Desktop\test.txt", "r") as f:
for num, line in enumerate(f, 1):
d = r.findall(line)
if(d):
l = d[0].split(":")
m = l[1].split(" ")
m = m[1] + "."
ans.append(m)
line_no.append(num)

x = Options(ans, line_no)
print(x.a, x.n)



with open (r"C:\Users\dhvani\Desktop\test.txt", "r") as f:
for i, j in enumerate(ans):
j1 = j[0]
z = f.readlines()[j1 - 1]
print(z)
for n in range(j1 - 1, j1 - 7, -1):
value = f.readline()
value1 = re1.findall(value)

if value1:
if value1 == i:
value.sub('[A-F]\.\s', '*', value)
break;


I am able to fetch the line number of "ANSWER: D" and store 'D.' and its corresponding line number in two different lists.

Then later steps are unsuccessful.

Any help will be greatly appreciated.
I am new to Python.

Jan Jan
Answer

You could use the following code:

import re

with open("your_filename_here", "r") as fp:
    string = fp.read()

    rx = re.compile(r'''
                (?!^[A-E]\.)
                (?P<question>.+[\n\r])
                (?P<choices>[\s\S]+?)
                ^ANSWER:\ (?P<answer>[A-E])
                ''', re.MULTILINE | re.VERBOSE)

    rq = re.compile(r'^[A-E]\.\ (?P<choice>.+)')

    for match in rx.finditer(string):

        def repl(line, answer):
            if line.startswith(answer):
                line = rq.sub(r"*\1", line)
            else:
                line = rq.sub(r"\1", line)
            return line

        lines = [repl(line, match.group('answer')) 
                for line in match.group('choices').split("\n") 
                if line]

        block = match.group('question') + "\n".join(lines)
        print(block)

This splits your blocks into parts of question, choices and the answer and analyzes them afterwards. See a demo on ideone.com.