fortran中限制数组的输入范围

 

fortran中限制数组的输入范围

001、

root@ubuntu26:/home/test01/fortran02# ls
test01.f90
root@ubuntu26:/home/test01/fortran02# cat test01.f90      ## 测试程序
program test01_fortran
    implicit none

    integer :: a
    do                                                   ！利用do无限循环
        write(*, "(A)", advance="no") "input a: "
        read *, a

        if(a >= 2) then
            exit                               
        end if
        print *, "a must be >= 2!"
    end do
    print *, "a = ", a
end program test01_fortran
root@ubuntu26:/home/test01/fortran02# gfortran test01.f90 -Wall -O2 -o kkk
root@ubuntu26:/home/test01/fortran02# ls
kkk  test01.f90
root@ubuntu26:/home/test01/fortran02# ./kkk         ## 测试
input a: -8
 a must be >= 2!
input a: 1
 a must be >= 2!
input a: 3
 a =            3

。

 

002、

root@ubuntu26:/home/test01/fortran02# ls
test01.f90
root@ubuntu26:/home/test01/fortran02# cat test01.f90            ## 测试程序
program test01_fortran
    implicit none

    integer :: a

    a = 0
    do while(a < 2)                                          ！ 利用do while条件判断
        write(*, "(A)", advance="no") "input a: "
        read *, a

        if(a < 2) then
            print *, "a must be >= 2!"
        end if
    end do
    print *, "a = ", a

end program test01_fortran
root@ubuntu26:/home/test01/fortran02# gfortran test01.f90 -Wall -O2 -o kkk
root@ubuntu26:/home/test01/fortran02# ls
kkk  test01.f90
root@ubuntu26:/home/test01/fortran02# ./kkk        ## 测试
input a: 0
 a must be >= 2!
input a: -8
 a must be >= 2!
input a: 6
 a =            6

 。