A good answer might be:

Without the parentheses the second "+" would mean "string concatenation," not addition.

Input File for Sum Program

Here is an input file for use with this program. The file is named input.txt.

12
7

Here is a sample run of the program with this data file:

C:\users\default\JavaLessons>java AddTwo < input.txt

Enter first number:
Enter second number:
Sum: 19

C:\users\default\JavaLessons>

Warning: The input file for this program cannot contain any characters that are not part of an integer. The characters must be an optional leading + or - followed by digit characters '0' through '9'. This includes spaces in front of a number. The following input file will not work:

12
 7

QUESTION 9:

What is wrong with the second input file?