need some help writing shell script to add numbers

Question

basically writing a script that adds numbers supplied by user as arguments to the script. The number of arguments are unknown. Also have to check to make sure it is an int. The script should show result of numbers.

an example:

./addNumbers 10 5 10

sum is 25

#!/bin/bash # check if more than 1 argument has been supplied by the user. if[ $# -lt 1 ] then — 23908938, Apr 08 '18 at 20:12

Abhijit Pritam Dutta · Accepted Answer · 2018-04-09T16:48:38.317

-1

Here you go:-

sum=0
if [ $# -eq 0 ]; then
   echo "Not enough arguments provided"
   echo "Correct uses : $0 23 22 25"
   echo "You can provide any number of argument"
   exit 1
fi
while [ $# -gt 0 ]
do
    echo "$1"
    sum=$(($sum+$1))
    shift
done    
echo "sum is $sum"

Now you can try like:-

./addNumbers 1 2 3 4 5 6 7 8 9 10  11 12 13 14 15 16 17 ....... 100

Here line 1 is a variable setting sum to 0. Line 2 is checking to make sure there is a greater number than 0. Then you echo the first argument second argument etc. Every iteration it will print next argument from the argument list.

edited Apr 09 '18 at 16:48

answered Apr 08 '18 at 20:10

Abhijit Pritam Dutta

5,521
2
11
17

This will only work if exactly 9 arguments are supplied. – Gordon Davisson Apr 08 '18 at 20:25
@GordonDavisson, Thanks for your comment. I have modified my answer. – Abhijit Pritam Dutta Apr 08 '18 at 20:37
thanks! Just to clarify, line 1 is a variable setting sum to 0. line 2 is checking to make sure theres a greater number than 0. then you echo the first argument ? i just want to understand this better. – 23908938 Apr 08 '18 at 22:28
Yes true. I have added your comment in my answer so that other people also can understand this. – Abhijit Pritam Dutta Apr 09 '18 at 06:55
Thank you!! & another question.. say the user doesnt provide any arguments. I want it to reply back with a message – 23908938 Apr 09 '18 at 16:01
example of something I worked on:then echo "$0: usage: list of integers" exit 1 – 23908938 Apr 09 '18 at 16:01
Mels-MacBook-Pro:documents Mel$ ./addNumbers.sh 1 37 46 ./addNumbers.sh: line 16: unexpected EOF while looking for matching `"' ./addNumbers.sh: line 17: syntax error: unexpected end of file – 23908938 Apr 09 '18 at 16:34
nevermind I found the error! thank you!!!! – 23908938 Apr 09 '18 at 16:40
@Mel, is my answer helped? – Abhijit Pritam Dutta Apr 09 '18 at 16:41
It was extremely helpful, thanks so much. Line 4 just needs the closing quotation that was the error. thank you very much – 23908938 Apr 09 '18 at 16:47

need some help writing shell script to add numbers

1 Answers1