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+For this problem, you will be writing a function which 
+performs a 90 degree clockwise rotation of a 10x10 matrix.
+There is nothing special about a 10x10 matrix---we are just
+fixing the size so that you can read the input in a future
+assignment after you have learned about reading files,
+but before you have learned about dynamic memory allocation.
+
+In particular, you should write
+
+  void rotate(char matrix[10][10])
+
+in a file called rotate.c
+
+This function takes a 10 by 10 matrix of characters and rotates
+it 90 degrees clockwise, updating the matrix that was passed in
+(remember that arrays are pointers, so you will modify
+the array in the frame where it was created).
+
+As you have not yet learned to read from files, we have
+provided a compiled object file, read-matrix.o.  This
+object file has a main function which will read
+the input file (specified as a command line arugments
+to your program), call your rotate function, and
+then print the result.
+
+If you compiled your code (and linked with read-matrix.o)
+into a program called rotate-matrix, you might run it as
+
+./rotate-matrix sample.txt
+
+It will then print the resulting matrix, which in this case
+should look like the contents of the file sample.out.
+(Remember that you can use > to redirect the output
+of a program to a file, and use diff to compare
+the contents of two files).
+
+Note that you do not have to complete the rotation 'in place'.