Suppose you have a lot of files in a directory named Exercisei_j, where i and j are digits. Write a program that pads a 0 before j if j is a single digit. For example, a file named Exercise2_1 in a directory will be renamed to Exercise     2_01. In Java, when you pass the symbol * from the command line, it refers to all files in the directory. Use the following command to run your program.