In this exercise, you are going to write a program to read input
from "/home2/solomon/WWW/Lang/C/vector1.dat".
You may copy the file to your working directory with the command
Then in your program, you can refer to the file by "vector1.dat" only,
without the full path.
The length of the data file is unknown, although we do know that in
each line there is exactly a string composed of one or two digits.
Therefore, you may need to use the skill of "indefinite loop" as in the
exercise of Input File Stream.
We shall store the strings in a vector, because the capacity of a vector
can increase whenever it is necessary.
In the loop, read a string from the data file, and print the string
out with a preceding serial number, as shown below.