你的fortran程序有两处问题,
1len=11写成了len-11
2weekday写成了weekend
完整的程序如下(改动的地方见注释)
PROGRAM weekday_weekend
IMPLICIT NONE
CHARACTER(len=11)::c_day
CHARACTER(len=11)::c_type !这里把(len-11)改成(len=11)
WRITE(*,*)'Enter the name of the day:'
READ(*,*)c_day
SELECT CASE(c_day)
CASE('Monday','Tuesday','Wednesday','Thursday','Friday')
c_type='Weekday' !这里把Weekend改成Weekday
CASE('Saturday','Sunday')
c_type='Weekend'
CASE DEFAULT
c_type='Invalid day'
END SELECT
WRITE(*,*)'Day Type=',c_type
END PROGRAM weekday_weekend