# -*- coding:utf-8 -*-
# @Author len
# @Create 2023/12/12 19:49

def if_formula(text):
    # 允许的字符：数字、运算符、括号、字母和空格
    allowed_chars = "0123456789+-*/(). abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ%^"
    operators = "+-*/%^"
    digits = "0123456789"
    letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"

    # 检查字符是否合法
    for char in text:
        if char not in allowed_chars:
            return False

    # 括号匹配检查
    bracket_count = 0
    for char in text:
        if char == '(':
            bracket_count += 1
        elif char == ')':
            bracket_count -= 1
        if bracket_count < 0:  # 右括号多于左括号
            return False
    if bracket_count != 0:  # 左括号和右括号数量不匹配
        return False

    # 去除空格，简化后续检查
    s = text.replace(' ', '')

    # 检查运算符、数字和字母的顺序
    if s and (s[0] in operators or s[-1] in operators):
        return False
    for i in range(1, len(s) - 1):
        if s[i] in operators and s[i + 1] in operators:
            # 防止两个运算符连续出现
            if not (s[i] in '-+' and s[i + 1] in '-+' and (s[i - 1] in operators or s[i - 1] == '(')):
                return False
        elif s[i] in digits and s[i + 1] in letters:
            # 防止数字紧跟字母
            return False
        elif s[i] in letters and s[i + 1] in digits:
            # 防止字母紧跟数字
            return False
        elif s[i] in letters and s[i + 1] in letters:
            # 防止连续的字母
            return False
        elif s[i] in '()' and s[i + 1] in letters and s[i] == ')':
            # 防止字母紧跟闭括号
            return False

    return True


list = ["124141", "AAAAAA", "AFF3241", "fafdafsfas",'A13C46', "124!@$%$%#@@#$%#@!@#$%#@!", "fsd65", "A1/2B%34", "((n*y+h)^4)/100"]
for i in list:
    if if_formula(i):
        print(i, "是")
    else:
        print(i, "不是")