perl -MData::Dumper -lne '@f=localtime((stat)[9]);$t{sprintf "%d%02d%02d",$f[5]+1900,$f[4]+1,$f[3]}+=(stat)[7];END{print Dumper \%t}'
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find .|perl -lne'$t{19000100+sprintf"%02d"x3,(localtime((stat)[9]))[5,4,3]}+=-s if!-d}{print"$_ $t{$_}"for sort keys%t'