First Second

AtCoder

IDagc047_b

Time3000ms

Memory256MB

Difficulty—

Limak can repeatedly remove one of the first two characters of a string, for example $abcxyx \rightarrow acxyx \rightarrow cxyx \rightarrow cyx$. You are given $N$ different strings $S_1, S_2, \ldots, S_N$. Among $N \cdot (N-1) / 2$ pairs $(S_i, S_j)$, in how many pairs could Limak obtain one string from the other? ## Constraints * $2 \leq N \leq 200\,000$ * $S_i$ consists of lowercase English letters `a`\-`z`. * $S_i \neq S_j$ * $1 \leq |S_i|$ * $|S_1| + |S_2| + \ldots + |S_N| \leq 10^6$ ## Input Input is given from Standard Input in the following format. $N$ $S_1$ $S_2$ $\vdots$ $S_N$ [samples]

Samples

Input #1

3
abcxyx
cyx
abc

Output #1

1

The only good pair is $(abcxyx, cyx)$.

Input #2

6
b
a
abc
c
d
ab

Output #2

5

There are five good pairs: $(b, abc)$, $(a, abc)$, $(abc, c)$, $(b, ab)$, $(a, ab)$.

API Response (JSON)

{
  "problem": {
    "name": "First Second",
    "description": {
      "content": "Limak can repeatedly remove one of the first two characters of a string, for example $abcxyx \\rightarrow acxyx \\rightarrow cxyx \\rightarrow cyx$. You are given $N$ different strings $S_1, S_2, \\ldots,",
      "description_type": "Markdown"
    },
    "platform": "AtCoder",
    "limit": {
      "time_limit": 3000,
      "memory_limit": 262144
    },
    "difficulty": "None",
    "is_remote": true,
    "is_sync": true,
    "sync_url": null,
    "sign": "agc047_b"
  },
  "statements": [
    {
      "statement_type": "Markdown",
      "content": "Limak can repeatedly remove one of the first two characters of a string, for example $abcxyx \\rightarrow acxyx \\rightarrow cxyx \\rightarrow cyx$.\nYou are given $N$ different strings $S_1, S_2, \\ldots,...",
      "is_translate": false,
      "language": "English"
    }
  ]
}

Full JSON Raw Segments