Fortran 95 Do While循环在错误条件下不退出

Fortran 95 Do While循环在错误条件下不退出,fortran,while-loop,exit,do-while,fortran95,Fortran,While Loop,Exit,Do While,Fortran95,这是我的密码: program change integer:: amount, remainder, q, d, n, p amount = 47 remainder = amount print*,remainder q = 0 d = 0 n = 0 p = 0 do w

这是我的密码:

program change 

            integer:: amount, remainder, q, d, n, p
            amount = 47
            remainder = amount
            print*,remainder
            q = 0
            d = 0
            n = 0
            p = 0

            do while (remainder >= 25)
                    remainder = remainder - 25
                    print*,remainder
                    q = q + 1       
            end do
            do while (remainder >= 10)
                    remainder = remainder - 25
                    print*,remainder
                    d = d + 1       
            end do
            do while (remainder >= 5)
                    remainder = remainder - 25
                    print*,remainder
                    n = n + 1       
            end do
            do while (remainder >= 1)
                    remainder = remainder - 25
                    print*,remainder
                    p = p + 1       
            end do 

            print*, "# Quarters:", q
            print*, "# Dimes:", d
            print*, "# Nickels:", n
            print*, "# Pennies:", p

    end program change
输出:

 47
      22
      -3
# Quarters:           1
# Dimes:           1
# Nickels:           0
# Pennies:           0

第一个循环(>=25)应该在余数变为22后退出,但它再次运行并产生一个负数。为什么即使条件为假,也不退出?我使用的是IDEone.com的Fortran“编译器”,看起来像Fortran 95。

您的DO循环很好。您只需从每个循环中的
余数
中减去正确的面额即可。例如,将第二个DO循环更改为:

        do while (remainder >= 10)
                remainder = remainder - 10
                print*,remainder
                d = d + 1       
        end do
并以类似的方式改变其余部分