def length_converter():
    # 使用字典存儲轉(zhuǎn)換系數(shù)，便于維護(hù)和擴(kuò)展
    units = {
        '米': 1,
        '千米': 1000,
        '厘米': 0.01,
        '毫米': 0.001,
        '英寸': 0.0254,
        '英尺': 0.3048,
        '英里': 1609.34,
        '碼': 0.9144
    }
    
    print("\n可選單位：", ', '.join(units.keys()))
    from_unit = input("請輸入原單位：").strip()
    to_unit = input("請輸入目標(biāo)單位：").strip()
    
    if from_unit not in units or to_unit not in units:
        print("錯(cuò)誤：無效的單位！")
        return

    try:
        value = float(input("請輸入要轉(zhuǎn)換的數(shù)值："))
    except ValueError:
        print("錯(cuò)誤：請輸入有效數(shù)字！")
        return

    meters = value * units[from_unit]
    result = meters / units[to_unit]
    print(f"\n轉(zhuǎn)換結(jié)果：{value} {from_unit} = {result:.4f} {to_unit}\n")

def temperature_converter():
    print("\n溫度單位：C（攝氏度）, F（華氏度）, K（開爾文）")
    from_unit = input("請輸入原單位（C/F/K）：").upper()
    to_unit = input("請輸入目標(biāo)單位（C/F/K）：").upper()
    
    try:
        temp = float(input("請輸入溫度值："))
    except ValueError:
        print("錯(cuò)誤：請輸入有效數(shù)字！")
        return

    # 統(tǒng)一轉(zhuǎn)換為攝氏度計(jì)算
    if from_unit == 'C':
        celsius = temp
    elif from_unit == 'F':
        celsius = (temp - 32) * 5/9
    elif from_unit == 'K':
        celsius = temp - 273.15
    else:
        print("錯(cuò)誤：無效的溫度單位！")
        return

    # 從攝氏度轉(zhuǎn)換到目標(biāo)單位
    if to_unit == 'C':
        result = celsius
    elif to_unit == 'F':
        result = (celsius * 9/5) + 32
    elif to_unit == 'K':
        result = celsius + 273.15
    else:
        print("錯(cuò)誤：無效的溫度單位！")
        return

    print(f"\n轉(zhuǎn)換結(jié)果：{temp:.2f}°{from_unit} = {result:.2f}°{to_unit}\n")

def currency_converter():
    print("\n貨幣轉(zhuǎn)換需要匯率，1單位原貨幣等于多少目標(biāo)貨幣")
    try:
        rate = float(input("請輸入?yún)R率："))
        amount = float(input("請輸入要轉(zhuǎn)換的金額："))
    except ValueError:
        print("錯(cuò)誤：請輸入有效數(shù)字！")
        return

    result = amount * rate
    print(f"\n轉(zhuǎn)換結(jié)果：{amount:.2f} 原貨幣 = {result:.2f} 目標(biāo)貨幣\n")