program listdemo
c       This program computes the mean, maximum, minimum, and
c       range of a list of numbers. The list is input by the user.        
        real list(100), mean, max, min, range
        integer n
        print *, "How many numbers are on your list ?"
        print *, "No more than 100, please."
        read *, n
        do i = 1, n
                print *, "Enter your next number :"
                read *, list(i)
        end do

        call data(n,list,mean,max,min)
        print *
        print *, "The mean is", mean
        print *, "The maximum is", max
        print *, "The minimum is", min
        print *, "The range is", max - min
        print *, "Bye"
        end

        subroutine data(n,list,mean,max,min)
        real list(100), mean, max, min, sum
        integer n
        sum = 0
        max = list(1)
        min = list(1)
        do i = 1, n
                sum = sum + list(i)
                if (list(i) .gt. max) max = list(i)
                if (list(i) .lt. min) min = list(i)
        end do
        mean = sum/n
        end