String Streams

1. Write a program to automatically generate 100 text files. The filenames are "a00.txt", "a01.txt", "a02.txt", ..., "a99.txt".
2. Each file contains 20 lines of integers. "a00.txt" contains

   0
   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19  

   "a01.txt" contains

   1
   2
   3
   4
   5
   6
   7
   8
   9
   10
   11
   12
   13
   14
   15
   16
   17
   18
   19
   20  

   and so on.
3. Use the techniques of file streaming and string streaming which you learned in Chapter 18 to write this program.