checkRow: Check a row for correctness.

This method takes a $2$D array and a row number. The method then checks if that row is correct in

the $2$D array. Note that, the row number starts from one; but, in a $2$D array, the row index would

start from zero. The method returns true if the times table for that row is correct, returns false

otherwise. The first line of the input file will have the row number to check. There will be only

one row to check. Based on the result the main method would either print