Finding number of repeats inside a list in a file with Python

Question

I need to find the number of times an entry in the list repeats consecutively. For example, consider the following file

"hello hello [A B C]"
"my world [D C F L]"
"tick tock [A L]"

In this file, the number of times C repeats is 2
A repeat is not counted as it is not repeating consecutively.

I am not sure of using re as it wouldnt tell me if it repeats consecutively. Any help would be apprecited.

Answer 1

the most simple way is to use re to parse the file.

regular expression that could work : \\[([AZ]\\s)+[AZ]\\]

then with the list of "list string" (aka ["[ABC]","[ FGR]"] ) convert it to a list.

the format must be like this for "[ABC]" "ABC", so remove spaces and [] for each one.

converted_string_list = list(str_list)

so a print converted_string_list will result in a list like this one for a string like "ADF":

['A', 'D', 'F']

then merge all list and find duplicates.

this is straigh forward solution! I am sure a better solution exists

Answer 2

For counting the duplicates once you get them into a list:

initial_length = len(my_list)
new_length = len(set(my_list))
duplicates = initial_length - new_length

Answer 3

def find_repeats_in_list(lines):
    # get lists from every line
    all_items = []
    for line in lines:
        open_bracket = line.index('[')
        close_bracket = line.index(']')
        items = line[open_bracket+1:close_bracket].split()
        all_items.append(items)

    # initialize dictionaries to hold consecutive counts
    counts = dict()
    final = dict()

    # seed counts with list from first line
    for item in all_items[0]:
        counts[item] = 1

    # check for first line list items in subsequent lines
    for items in all_items[1:]:
        for counted in counts:
            remove = []
            if counted not in items:      # not in current line, stop counting
                remove.append(counted)
                if counts[counted] > 1:   # but put in final if more than one
                    final[counted] = counts[counted]
        for item in remove:
            del counts[item]
        for item in items:                # now increment anything consecutive
            if item in counts:
                counts[item] += 1
    return final