# 存储计算历史记录
history = []

# 基础运算功能
def basic_calculation():
    try:
        num1 = float(input("请输入第一个数字："))
        num2 = float(input("请输入第二个数字："))
        operator = input("请输入运算符号（+、-、*、/）：")
        # 计算逻辑
        if operator == "+":
            result = num1 + num2
        elif operator == "-":
            result = num1 - num2
        elif operator == "*":
            result = num1 * num2
        elif operator == "/":
            if num2 == 0:
                print("错误：除数不能为0！")
                return
            result = num1 / num2
        else:
            print("错误：无效的运算符号！")
            return
        # 记录计算历史
        record = f"{num1} {operator} {num2} = {result:.2f}"
        history.append(record)
        print(f"计算结果：{result:.2f}")
    except ValueError:
        print("输入格式错误，请输入数字！")

# 十进制转二进制
def decimal_to_binary():
    try:
        decimal_num = int(input("请输入要转换的十进制整数："))
        if decimal_num < 0:
            print("请输入非负整数！")
            return
        binary_num = bin(decimal_num)[2:]  # bin()返回值带'0b'前缀，切片去掉
        record = f"十进制{decimal_num} 转二进制 = {binary_num}"
        history.append(record)
        print(f"十进制{decimal_num}转换为二进制的结果：{binary_num}")
    except ValueError:
        print("输入格式错误，请输入整数！")

# 二进制转十进制
def binary_to_decimal():
    binary_str = input("请输入要转换的二进制数（仅含0和1）：")
    # 验证二进制格式
    if not all(c in "01" for c in binary_str):
        print("错误：输入的不是二进制数！")
        return
    decimal_num = int(binary_str, 2)
    record = f"二进制{binary_str} 转十进制 = {decimal_num}"
    history.append(record)
    print(f"二进制{binary_str}转换为十进制的结果：{decimal_num}")

# 查看历史记录
def show_history():
    if history:
        print("\n===== 计算历史记录 =====")
        for i, record in enumerate(history, 1):
            print(f"{i}. {record}")
    else:
        print("暂无计算历史记录！")

# 清除历史记录
def clear_history():
    global history
    history = []
    print("历史记录已清除！")

# 主菜单
def main():
    while True:
        print("\n===== 简易计算器 =====")
        print("1. 基础运算（+、-、*、/）")
        print("2. 十进制转二进制")
        print("3. 二进制转十进制")
        print("4. 查看计算历史")
        print("5. 清除计算历史")
        print("6. 退出系统")
        choice = input("请输入您的选择（1-6）：")
        if choice == "1":
            basic_calculation()
        elif choice == "2":
            decimal_to_binary()
        elif choice == "3":
            binary_to_decimal()
        elif choice == "4":
            show_history()
        elif choice == "5":
            clear_history()
        elif choice == "6":
            print("感谢使用，再见！")
            break
        else:
            print("输入错误，请重新选择！")

if __name__ == "__main__":
    main()