in reply to adding values of element

Try this one-liner: 
perl -anF/[\\s,]+/ -e '$tot{$F[0]}+=$F[1]}{print qq|$tot{$_}\t$_\n| fo
+r sort keys %tot' <YOUR-FILE-NAME>

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Note the extra "\" for the shell (Linux assumed).

        "You're only given one little spark of madness. You mustn't lose it."         - Robin Williams

In Section Seekers of Perl Wisdom