#
#  Computes the sum of all of the numbers in a file, and displays the sum
#  on the screen.
#
import sys

# Read the name of the file from the user, and open that file for reading.
if len(sys.argv) == 1:  # There is no command line argument
  fname = input("Enter the name of a file that contains numbers: ")
else:
  fname = sys.argv[1]  # Get the name from the command line

inf = open(fname, "r")

# Initiaize a variable for the sum to 0.
total = 0

# Process each line, adding its number to the sum.
line = inf.readline()   # Read the first line from the file
while line != "":
  total = total + float(line)
  line = line.strip("\n")
  print(f"Adding {line} to the total which is now {total}...")

  line = inf.readline()  # Read the next line from the file

# Close the file.
inf.close()

# Display the sum.
print(f"The sum of the values in {fname} is {total}.")