实例0831书中说不需要声明就可以用，但是出现报错

DDHH

[Fortran] 纯文本查看 复制代码

program ex0831
implicit none
integer ::n
write(*,*)'N='
read (*,*)n
write(*,"(I2,'!=',I8)")n,fact(n)
stop
end

contains
recursive integer function fact(n)result(ans)
implicit none
integer ,intent(in)::n

if (n<0)then
ans=-1
return
else if (n<=1)then
ans =1
return
end if
ans=n*fact(n-1)
return
end function fact
end

--------------------Configuration: 21351 - Win32 Debug--------------------
Compiling Fortran...
E:\Fortran\MSDEV98\MyProjects\21351\320020.f90
E:\Fortran\MSDEV98\MyProjects\21351\320020.f90(6) : Error: This name does not have a type, and must have an explicit type.   [FACT]
write(*,"(I2,'!=',I8)")n,fact(n)
-------------------------^
Error executing df.exe.

21351.exe - 1 error(s), 0 warning(s)