map{split;${"''$_[0]'"}+=$_[1]}<DATA>;map{/^'(.*)'$/&&say$1,$",${"''$1
+'"}}%::; 

__DATA__
AA 12
bb 34
AA 76
cc 98
dd 76
bb 98
__END__
bb 132
dd 76
cc 98
AA 88
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Quiz: explain all the quotes.