How about you show us some code you have tried? Why didn't you read the site documentation that tells you how to format your node?

True laziness is hard work

In reply to Re: find unique elments and sum the corresponding values by GrandFather
in thread find unique elments and sum the corresponding values by Prl_learner

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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