<?php
fscanf(STDIN, '%d', $cnt);
$words = [];
for ($i=0; $i < $cnt; $i++) {
$words[] = str_split(trim(fgets(STDIN)));
}
$len = count($words);
$temps = [];
for ($i=0; $i < $len; $i++) {
asort($words[$i]);
$temps[] = implode('', $words[$i]);
}
$acv = array_count_values($temps);
$ans = 0;
foreach ($acv as $key => $value) {
if ($value > 2) {
$ans += ($value * ($value - 1)) / 2;
} elseif ($value === 2) {
$ans += 1;
}
}
echo $ans;