Arrays 如何在Fortran中设置一个小代码复活节彩蛋-随机选择错误消息的引号

我创建了一个程序，它有一个用户界面，可以从菜单中选择一个选项。此选项被馈送到if语句，该语句将其重定向到正确的子例程。我还设置了一个小错误消息，以防选项输入错误

        else
        write(*,*)''
        write(*,*)''
        write(*,*)''
        write(*,*)'I am sorry, Dave. I am afraid I cannot do that!' 
        write(*,*)''
        write(*,*)''
        write(*,*)''
        write(*,*)' Press enter to return to main menu! '
        read(*,*)
        goto 300
    end if 

一切都很好。事实是-HAL9000有很多标志性短语，它们可能会像错误消息一样棒，因此我想改进这个

if block

，为用户提供从一组预定义短语中随机选择的短语。这些短语的示例：

    'This mission is too important for me to allow you to jeopardize it.'
    'I know I've made some very poor decisions recently, but I can give you my complete assurance that my work will be back to normal.'
    'I've still got the greatest enthusiasm and confidence in the mission. And I want to help you.'
    'Just what do you think you're doing, Dave?'
    'Look Dave, I can see you're really upset about this.'
    'I honestly think you ought to sit down calmly, take a stress pill, and think things over.'

好吧，起初我认为这很简单：只需构建一个字符数组，弹出其中的短语，然后执行以下操作：

program pick_random
  implicit none
 
  integer :: i
  integer :: a(10) = (/ (i, i = 1, 10) /)
  real :: r
 
  call random_seed
  call random_number(r)
  write(*,*) a(int(r*size(a)) + 1)
end program

但很明显，Fortran似乎不是这样工作的，字符数组显然有一个我所希望的

关于如何实现它，有什么建议吗？

在对我的源代码中缺少的概念进行了宝贵的评论之后，我成功地创建了代码，并且工作得很好！为了将来的参考，我会把它贴在这里

  subroutine easter_eggs()
    implicit none
    character(len=100),dimension(8) :: easter_egg
    integer :: i
    real :: r
   


easter_egg=(/&
        &'Are you from the future? Because I have not written such option yet! Wierd...!                      ',&
        &'Mistakes allow thinking to happen!                                                                  ',&
        &'Let me state the obvious: Are you sure you type the keyword correctly?                              ',&
        &'There are no easter eggs in this program. Yep! That is right! None! And you there is no such option!',&
        &'You have learned so much from your mistakes that you decided to make a few more, right?             ',&
        &'Just what do you think you are doing, Dave?                                                         ',&
        &'I see you never do the same mistake twice - you like to do it often just to be sure!                ',&
        &'Anyone who has never made a mistake has never tried anything new! (Albert Einstein)                 '/)
    
    call random_seed
    call random_number(r)
    write(*,*)easter_egg(int(r*size(easter_egg))+1)
    
    end subroutine easter_eggs

---

跟进：根据@francescalus的建议，我尝试将字符数组重写如下

---

---

它编译得很好，但每次我输入一个错误的关键字时，只会弹出一个短语——与字符数组中设置的第一个短语对应的短语

您能用字符数组显示您的尝试吗？如果我这样做的话，这正是我希望使用的。可能参考文章中缺少的必要概念是，可以定义特定长度的字符变量数组，例如

character（len=32），dimension（24）：：random_strings

。正如我们所说的，Bob是你母亲的兄弟。字符数组构造函数有一个很好的例子，它可以避免用空格进行痛苦的填充。请注意，上面使用的

调用random\u seed

可能有问题。Fortran标准没有定义此调用是使用一组新的种子为PRNG设定种子，还是使用一组处理器相关的种子为PRNG重新设定种子。因此，

r

可能总是具有相同的值。最好使用

random\u init

。它完全跳过了我！而且，奇怪的是编译器怎么没有标记它！使用

random_init（.true.，…）

可以请求一个可重复的流。这意味着你每次都得到相同的号码。使用

.false.

获取不同的（不可重复的）数字。

   subroutine easter_eggs()
    implicit none      
    integer :: i
    real :: r
    character(len=100),dimension(8) :: easter_egg = [ character(len=100) :: &
    &"Are you from the future? Because I have not written such option yet! Wierd...!",&
    &"Mistakes allow thinking to happen!",&
    &"Let me state the obvious: Are you sure you type the keyword correctly?",&
    &"There are no easter eggs in this program. Yep! That is right! None! And you there is no such option!",&
    &"You have learned so much from your mistakes that you decided to make a few more, right?",&
    &"Just what do you think you are doing, Dave?",&
    &"I see you never do the same mistake twice - you like to do it often just to be sure!",&
    &"Anyone who has never made a mistake has never tried anything new! (Albert Einstein)"]

    call random_init(.true., .true.)
    call random_number(r)
    write(*,*)easter_egg(int(r*size(easter_egg))+1)

    end subroutine easter_eggs

    end module formalism