{"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 same character occurs multiple times, that character must be used that number of times.\nGiven 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 $s_j$.\n\n## Constraints\n\n*   $2 \\leq N \\leq 10^5$\n*   $s_i$ is a string of length $10$.\n*   Each character in $s_i$ is a lowercase English letter.\n*   $s_1, s_2, \\ldots, s_N$ are all distinct.\n\n## Input\n\nInput is given from Standard Input in the following format:\n\n$N$\n$s_1$\n$s_2$\n$:$\n$s_N$\n\n[samples]","is_translate":false,"language":"English"}],"meta":{"iden":"abc137_c","tags":[],"sample_group":[["3\nacornistnt\npeanutbomb\nconstraint","1\n\n$s_1 =$ `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 $1$."],["2\noneplustwo\nninemodsix","0\n\nIf there is no pair $i, j$ such that $s_i$ is an anagram of $s_j$, print $0$."],["5\nabaaaaaaaa\noneplustwo\naaaaaaaaba\ntwoplusone\naaaabaaaaa","4\n\nNote that the answer may not fit into a $32$\\-bit integer type, though we cannot put such a case here."]],"created_at":"2026-03-03 11:01:13"}}