Green Bin

AtCoder

IDabc137_c

Time2000ms

Memory256MB

Difficulty—

We will call a string obtained by arranging the characters contained in a string $a$ in some order, an _anagram_ of $a$. For example, `greenbin` is an anagram of `beginner`. As seen here, when the same character occurs multiple times, that character must be used that number of times. Given are $N$ strings $s_1, s_2, \ldots, s_N$. Each of these strings has a length of $10$ and consists of lowercase English characters. Additionally, all of these strings are distinct. Find the number of pairs of integers $i, j$ $(1 \leq i < j \leq N)$ such that $s_i$ is an anagram of $s_j$. ## Constraints * $2 \leq N \leq 10^5$ * $s_i$ is a string of length $10$. * Each character in $s_i$ is a lowercase English letter. * $s_1, s_2, \ldots, s_N$ are all distinct. ## Input Input is given from Standard Input in the following format: $N$ $s_1$ $s_2$ $:$ $s_N$ [samples]

Samples

Input #1

3
acornistnt
peanutbomb
constraint

Output #1

1

$s_1 =$ `acornistnt` is an anagram of $s_3 =$ `constraint`. There are no other pairs $i, j$ such that $s_i$ is an anagram of $s_j$, so the answer is $1$.

Input #2

2
oneplustwo
ninemodsix

Output #2

0

If there is no pair $i, j$ such that $s_i$ is an anagram of $s_j$, print $0$.

Input #3

5
abaaaaaaaa
oneplustwo
aaaaaaaaba
twoplusone
aaaabaaaaa

Output #3

4

Note that the answer may not fit into a $32$\-bit integer type, though we cannot put such a case here.

API Response (JSON)

{
  "problem": {
    "name": "Green Bin",
    "description": {
      "content": "We will call a string obtained by arranging the characters contained in a string $a$ in some order, an _anagram_ of $a$. For example, `greenbin` is an anagram of `beginner`. As seen here, when the sam",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 2000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "abc137_c"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "We will call a string obtained by arranging the characters contained in a string $a$ in some order, an _anagram_ of $a$.\nFor example, `greenbin` is an anagram of `beginner`. As seen here, when the sam...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments