Calculating the sum of two variables in a batch script

batch-file, dosbox, variables

Solution

You need to use the property `/a` on the set command.

For example,

set /a "c=%a%+%b%"

This allows you to use arithmetic expressions in the set command, rather than simple concatenation.

Your code would then be:

@set a=3
@set b=4
@set /a "c=%a%+%b%"
echo %c%
@set /a "d=%c%+1"
echo %d%

and would output:

7
8

Problem

This is my first time on Stack Overflow so please be lenient with this question. I have been experimenting with programming with batch and using DOSbox to run them on my linux machine. Here is the code I have been using: ``` @echo off set a=3 set b=4 set c=%a%+%b% echo %c% set d=%c%+1 echo %d% ``` The output of that is: ``` 3+4 3+4+1 ``` How would I add the two variables instead of echoing that string?

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