#!/usr/bin/perl
use warnings;
use strict;

my %violations_by_category;
my $category;
while (<DATA>) {
    if (/^([A-Z])_[0-9]+:/) {
        $category = $1;

    } elsif (/([0-9]+) violations?/) {
        $violations_by_category{$category} += $1;
    }
}

for my $category (keys %violations_by_category) {
    print $category, " ", $violations_by_category{$category}, "\n";
}

__DATA__
A_01: xxxxxxx
xxxxxxxxxx
xxx......... 1 violation

A_02: xxxxxxx
xxxxxxxxxx
xxx......... 4 violations
B_02: xxxxxxxx
xxxxxxxxxx
xxx......... 3 violations