Letters And Numbers
Given an array filled with letters and numbers, fnd the longest subarray with an equal number of letters and numbers :param string: string :return: subarray
from collections import Counter
def equal_number_of_letters_and_numbers(string: str):
"""
Given an array filled with letters and numbers, fnd the longest subarray with
an equal number of letters and numbers
:param string: string
:return: subarray
"""
number_count = []
letter_count = []
# count the number of letters and numbers
for i in string:
if i.isdigit():
number_count.append(1 if len(number_count) == 0 else number_count[-1] + 1)
letter_count.append(0 if len(letter_count) == 0 else letter_count[-1])
else:
letter_count.append(1 if len(letter_count) == 0 else letter_count[-1] + 1)
number_count.append(0 if len(number_count) == 0 else number_count[-1])
diff = []
# Calculate the difference in each position
for i in range(0, len(number_count)):
diff.append(letter_count[i] - number_count[i])
print(' '.join(map(lambda x: str(x).center(3), list(range(0, len(diff))))))
print(' '.join(map(lambda x: str(x).center(3), list(string))))
print(' '.join(map(lambda x: str(x).center(3), letter_count)))
print(' '.join(map(lambda x: str(x).center(3), number_count)))
print(' '.join(map(lambda x: str(x).center(3), diff)))
# the result is the furthest value of same difference
counter = Counter(diff)
largest_diff_range = (None, None)
largest_index = (None, None)
for (value, counts) in counter.most_common():
if counts <= 1:
continue
first_index = diff.index(value)
last_index = len(diff) - 1 - list(reversed(diff)).index(value)
difference = last_index - first_index
if largest_diff_range[0] is None or difference > largest_diff_range[0]:
largest_diff_range = (difference, value)
largest_index = (first_index, last_index)
# first substring starts from +1 of the range
result = string[largest_index[0] + 1: largest_index[1] + 1]
print(result)
return result
if __name__ == "__main__":
equal_number_of_letters_and_numbers("aaaa11a11aa1aa1aaaaa")
Updated on 2020-12-05