面试题：Fortran时间日期函数复杂应用

Question

假设你有一个包含一系列时间点（格式为YYYY - MM - DD HH:MM:SS）的文本文件，使用Fortran语言，结合时间日期函数，统计出这些时间点中每个月出现的次数，并按月份顺序输出结果，写出完整的程序代码。

Answer 1

program count_months
    implicit none
    character(len=20) :: line
    integer :: i, unit_num, month, count(12)
    integer :: year, day, hour, minute, second
    count = 0

   ! 打开文件
    open(newunit = unit_num, file = 'time_points.txt', status = 'old')

    do
       ! 逐行读取文件
        read(unit_num, '(a)', end = 100) line
        read(line, '(i4,i1,i2,i1,i2,i1,i2,i1,i2,i1,i2)') year, month, day, hour, minute, second
        count(month) = count(month) + 1
    end do
100 continue

   ! 输出结果
    do i = 1, 12
        write(*, '(i2, ": ", i5)') i, count(i)
    end do

   ! 关闭文件
    close(unit_num)
end program count_months