Problem7138--ABC268 —— F - Best Concatenation

7138: ABC268 —— F - Best Concatenation

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Time Limit : 1.000 sec  Memory Limit : 256 MiB

Description

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

$2≤N≤2×10^5$
$N$ 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 1 Input

3
1X3
59
XXX

Sample 1 Output

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 2 Input

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

Sample 2 Output

3010

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