1957. Delete Characters to Make Fancy String

easy, String

A fancy string is a string where no three consecutive characters are equal.

Given a string s, delete the minimum possible number of characters from s to make it fancy.

Return the final string after the deletion. It can be shown that the answer will always be unique.

Example 1:

Input: s = “leeetcode”
Output: “leetcode”
Explanation:
Remove an ‘e’ from the first group of ‘e’s to create “leetcode”.
No three consecutive characters are equal, so return “leetcode”.

Example 2:

Input: s = “aaabaaaa”
Output: “aabaa”
Explanation:
Remove an ‘a’ from the first group of ‘a’s to create “aabaaaa”.
Remove two ‘a’s from the second group of ‘a’s to create “aabaa”.
No three consecutive characters are equal, so return “aabaa”.

Example 3:

Input: s = “aab”
Output: “aab”
Explanation: No three consecutive characters are equal, so return “aab”.

## code

import os
import logging
import traceback
import datetime


def get_logger(LEVEL: str = "INFO") -> logging.Logger:
    # log_time = datetime.datetime.today().strftime("%Y-%m-%d_%H-%M-%S")

    logger = logging.getLogger("custom_logger")
    logger.setLevel(getattr(logging, LEVEL.upper(), logging.INFO))

    # file_handler = logging.FileHandler(f"./logs/{log_time}_logfile.log")
    stream_handler = logging.StreamHandler()

    formatter = logging.Formatter(
        fmt="[%(asctime)s %(levelname)s] %(message)s", datefmt="%Y/%m/%d %H:%M:%S"
    )
    # file_handler.setFormatter(formatter)
    stream_handler.setFormatter(formatter)

    if logger.hasHandlers():
        logger.handlers.clear()

    # logger.addHandler(file_handler)
    logger.addHandler(stream_handler)

    return logger


def sol(problem_num, func):
    script_dir = os.getcwd()  # os.path.dirname(os.path.abspath(__file__))
    path = script_dir + f"\\txt\\{problem_num}" + ".txt"
    # logger.info(f"file path : {path}")

    try:
        with open(path, "r") as getter:
            line_count = 1
            while True:
                line = getter.readline()
                # logger.info(f"this line : {line.strip().split()}")
                if not line:
                    logger.info("EOF")
                    break
                try:
                    inp, oup = line.strip().split()
                    if not func(inp):
                        raise ValueError(f"wrong output in line : {line}")
                    logger.info(f"{line_count} : {inp} : {oup == func(inp)}")
                    line_count += 1
                except Exception as e:
                    logger.error(f"Error occurred while processing line: {line}")
                    logger.error(f"Exception: {e}")
                    logger.error(traceback.format_exc())
                    line_count += 1
    except FileNotFoundError:
        logger.error(f"File not found: {path}")
    except Exception as e:
        logger.error(f"Error opening file: {e}")
        logger.error(traceback.format_exc())
    logger.info("ACCEPT")


class Solution:
    def makeFancyString(self, s: str) -> str:
        result = ""

        grouped = []
        current_group = s[0]
        for char in s[1:]:
            if char == current_group[-1]:
                current_group += char
            else:
                grouped.append(current_group)
                current_group = char
        grouped.append(current_group)

        for group in grouped:
            if len(group) > 2:
                result += group[0] * 2
            else:
                result += group

        return result


problem_num = 1957
global logger
logger = get_logger("info")
sol(problem_num, Solution().makeFancyString)

[2024/11/01 14:11:20 INFO] 1 : leeetcode : True
[2024/11/01 14:11:20 INFO] 2 : aaabaaaa : True
[2024/11/01 14:11:20 INFO] EOF
[2024/11/01 14:11:20 INFO] ACCEPT

겁나 나는 뭔가 어렵게 풀었는데 다른 사람 코드 보니깐 어이가 없을 정도로 쉽게 푼 것을 확인할 수 있었다.

class Solution:
    def makeFancyString(self, s: str) -> str:
        ans = s[0]
        cnt = 1
        for i in range(1, len(s)):
            if s[i] == ans[-1]:
                cnt += 1
                if cnt < 3:
                    ans += s[i]
            else:
                cnt = 1
                ans += s[i]
        return ans

나는 for 문을 두번을 돌지만 여긴 한번만 돌면서 예외처리를 해버린다. 중요한 거슨 cnt += 를 사용하는 아이디어인 것으로 보인다.