# ==============================================================================
# 通过 D:\文档\电子文档\个人\脚本库\PythonScript\第2章.py + 题号 运行
# 程序名：
#   第2章习题
# 目的:
# 
# 修订记录:
#         日期              编程者               改动描述
# ===================   =============   =====================================
# 2021-07-20 21:29:18       Sola        2-1 介绍呗
# 2021-07-20 21:29:30       Sola        2-2 介绍完不自动退出
# 2021-07-20 21:29:42       Sola        2-3 计算平均分
# 2021-07-20 21:29:54       Sola        2-4 计算5次华氏度
# 2021-07-20 21:30:22       Sola        2-5 计算0~100℃对应华氏度
# 2021-07-20 21:30:47       Sola        2-6 本金利滚利
# 2021-07-20 21:31:11       Sola        2-7 追加利滚利
# 2021-07-20 21:31:21       Sola        2-8 利滚利滚利(我是有极限的！)
# 2021-07-20 21:35:18       Sola        2-9 华氏度转摄氏度
# 2021-07-20 21:38:07       Sola        2-10 千米转英里
# 2021-07-20 21:42:45       Sola        2-11 任意一个单位转换 略
# 2021-07-20 21:42:59       Sola        2-12 Python计算器

def test2_1():
    print("Hello, World! 这里我就懒得再改介绍了，怪麻烦的。")

def test2_2():
    print("Hello, World! 这里我就懒得再改介绍了，怪麻烦的。")
    input("Press the <Enter> key to quit.")

def test2_3():
    print("This program computes the average of two exam scores.")
    score1, score2, score3 = eval(input("Enter three scores separated by a comma: "))
    average = (score1 + score2 + score3) / 3
    print("The average of the scores is:", average)

def test2_4():
    for i in range(5):
        celsius = eval(input("What is the Celsius temperature? "))
        fahrenheit = 9/5 * celsius + 32
        print("The temperature is", fahrenheit, "degrees Fahrenheit.")

def test2_5():
    celsius = 0
    print("摄氏度(℃)\t华氏度(℉)")
    for i in range(11):
        fahrenheit = 9/5 * celsius + 32
        print('', celsius, "\t\t", fahrenheit)
        celsius = celsius + 10

def test2_6():
    print("This program calculates the future value of a investment.")
    principal = eval(input("Enter the initial principal: "))
    years = eval(input("Enter the number of years of your investment: "))
    apr = eval(input("Enter the annual interest rate: "))
    for i in range(years):
        principal = principal * (1 + apr)
    print("The value in", years, "years is:", principal)

def test2_7():
    print("This program calculates the future value of a investment.")
    investment = eval(input("Enter the annual investment: "))
    years = eval(input("Enter the number of years of your investment: "))
    apr = eval(input("Enter the annual interest rate: "))
    principal = investment
    for i in range(years):
        principal = principal * (1 + apr) + investment
    print("The value in", years, "years is:", principal)

def test2_8():
    print("This program calculates the future value of a investment.")
    principal = eval(input("Enter the initial principal: "))
    years = eval(input("Enter the number of years of your investment: "))
    times = eval(input("Enter the number of interest calculations per year: "))
    apr = eval(input("Enter the annual interest rate: "))
    for i in range(years):
        for j in range(times):
            principal = principal * (1 + apr / times)
    print("The value in", years, "years is:", principal)

def test2_9():
    fahrenheit = eval(input("What is the Fahrenheit temperature? "))
    celsius = 5/9 * ( fahrenheit - 32 )
    print("The temperature is", celsius, "degrees celsius.")

def test2_10():
    km = eval(input("请输入千米数: "))
    print(km, "km =", 0.62 * km, "mile")

def test2_11():
    print("太简单，略过，，，实在懒得再重写一个了")

def test2_12():
    print("Python 交互式科学计算器")
    for i in range(100):
        expr = input("请输入算数表达式：")
        a = eval(expr)
        print(expr, "的结果为", a, "，您还可以计算", 99 - i, "次")

import sys
def run(num):
    eval("test2_" + num + "()")
run(sys.argv[1])