How to Google+ +1 CodeChef Problem

I recently +1ed the OCT15 Rankings and made a post about the current CodeChef Long competition using the

G+1

button in the top-left corner. I remember this used to be on problem statements, too. However, when I go to a problem statement now (here’s an example), I can’t find the

G+1

button. I can easily make a Google+ post manually and include the link to the problem, but I am curious about how I can make a Google+ post about a problem from the CodeChef Web site like with the rankings. Thank you for looking at this, CodeChef!

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