P25866 [AtCoder] Best Concatenation
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题目描述

Problem Statement

You are given $N strings S_1, S_2, \ldots, S_N$ consisting of digits from 1 through 9 and the character X.
We will choose $a permutation P = (P_1, P_2, \ldots, P_N)$ of $(1, 2, \ldots, N)$
to construct $a string T = S_{P_1} + S_{P_2} + \cdots + S_{P_N}$, where + denotes a concatenation of strings.
Then, we will calculate the "score" of the string $T = T_1T_2\ldots T_{|T|} ($where |T| denotes the length of T).
The score is calculated by the following 9 steps, starting from the initial score 0:

  • Add 1 point to the score as many times as the number of integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 1.
  • Add 2 points to the score as many times as the number of integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 2.
  • Add 3 points to the score as many times as the number of integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 3.
  • $\cdots$
  • Add 9 points to the score as many times as the number of integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 9.

Find the maximum possible score of T when P can be chosen arbitrarily.

Input

Input is given from Standard Input in the following format:
N
S_1
S_2
$\vdots$
S_N

Output

Print the answer.

Constraints

  • $2 \leq N \leq 2 \times 10^5$
  • N is an integer.
  • S_i is a string of length at least 1 consisting of digits from 1 through 9 and the character X.
  • The sum of lengths of $S_1, S_2, \ldots, S_N$ is at most $2 \times 10^5$.

Sample Input 1

3
1X3
59
XXX

Sample Output 1

71

When P = (3, 1, 2), we have T = S_3 + S_1 + S_2 = XXX1X359.
Then, the score of T is calculated as follows:

  • there are 3 integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 1;
  • there are 4 integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 3;
  • there are 4 integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 5;
  • there are 4 integer pairs (i, j) such that $1 \leq i \lt j \leq |T|, T_i = X$, and T_j = 9.

Therefore, the score of T is $1 \times 3 + 3 \times 4 + 5 \times 4 + 9 \times 4 = 71,$ which is the maximum possible value.

Sample Input 2

10
X63X395XX
X2XX3X22X
13
3716XXX6
45X
X6XX
9238
281X92
1XX4X4XX6
54X9X711X1

Sample Output 2

3010

输入格式

见题面 Input 部分

输出格式

见题面 Output 部分

样例输入
3 1X3 59 XXX
样例输出
71