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Time Limit: 1 s Memory Limit: 1024 MB Total points: 100

#3735. 反转

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Bobo 有一个 $n$ 位的十进制数 $D = d_1d_2\dots d_n$(它可能包含前导零)。

令 $R(i, j)$ 表示将数 $D$ 中第 $i$ 位到第 $j$ 位之间的数字翻转后得到的数。即 $R(i, j) = d_1\dots d_{i - 1} d_jd_{j - 1}\dots d_i d_{j + 1}d_{j + 2}\dots d_n$。

Bobo 想要计算 $$ \sum_{i = 1}^n \sum_{j = i}^n R(i, j) $$ 对 $(10^9+7)$ 取模的结果。

输入包含最多 $30$ 组数据。对于每组数据:

第一行包含一个整数 $n$ ($1 \leq n \leq 10^5$)。

第二行包含 $n$ 个数字 $d_1d_2\dots d_n$ ($0 \leq d_i \leq 9$)。

对于每组数据,输出一个整数表示结果。

样例

输入格式 1

2
12
3
012
10
0123456789

输出格式 1

45
369
733424314

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