NickName:swarajd Ask DateTime:2012-05-21T00:00:27

Calculating the sum of two variables in a batch script

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?

Copyright Notice：Content Author:「swarajd」，Reproduced under the CC 4.0 BY-SA copyright license with a link to the original source and this disclaimer.
Link to original article：https://stackoverflow.com/questions/10674974/calculating-the-sum-of-two-variables-in-a-batch-script

Answers

staticbeast 2012-05-20T16:41:55

You need to use the property /a on the set command.\n\nFor example, \n\nset /a \"c=%a%+%b%\"\n\n\nThis allows you to use arithmetic expressions in the set command, rather than simple concatenation.\n\nYour code would then be:\n\n@set a=3\n@set b=4\n@set /a \"c=%a%+%b%\"\necho %c%\n@set /a \"d=%c%+1\"\necho %d%\n\n\nand would output:\n\n7\n8\n",

lolzeryest 2015-02-09T01:48:09

According to this helpful list of operators [an operator can be thought of as a mathematical expression] found here, you can tell the batch compiler that you are manipulating variables instead of fixed numbers by using the += operator instead of the + operator.\n\nHope I Helped!",

Richie 2016-10-25T04:13:20

You can solve any equation including adding with this code:\n\n@echo off\n\ntitle Richie's Calculator 3.0\n\n:main\n\necho Welcome to Richie's Calculator 3.0\n\necho Press any key to begin calculating...\n\npause>nul\n\necho Enter An Equation\n\necho Example: 1+1\n\nset /p \n\nset /a sum=%equation%\n\necho.\n\necho The Answer Is:\n\necho %sum%\n\necho.\n\necho Press any key to return to the main menu\n\npause>nul\n\ncls\n\ngoto main\n",

Luke 2016-05-17T03:53:18

@ECHO OFF\nTITLE Addition\nECHO Type the first number you wish to add:\nSET /P Num1Add=\nECHO Type the second number you want to add to the first number:\nSET /P Num2Add=\nECHO.\nSET /A Ans=%Num1Add%+%Num2Add%\nECHO The result is: %Ans%\nECHO.\nECHO Press any key to exit.\nPAUSE>NUL\n",

Tamil selvan 2014-08-07T11:29:09

@ECHO OFF\nECHO Welcome to my calculator!\nECHO What is the number you want to insert to find the sum?\nSET /P Num1=\nECHO What is the second number? \nSET /P Num2=\nSET /A Ans=%Num1%+%Num2%\nECHO The sum is: %Ans%\nPAUSE>NUL\n",