write a program to find the factorial of a given number (using goto command)

implicit double precision (a-h,o-z)
    iprod=1
    i=1
    write(*,*) 'n'
    read(*,*) n
10    if(i.LE.n) then
    iprod=iprod*i
    i=i+1
    goto 10
    else
    write(*,*) iprod
    goto 20
20    endif
      stop
      end