Codeforces Round 523 (Div. 2)
C
Multiplicity
Codeforces
1700
原题
← BD →
翻译中…

You are given an integer array $a_1, a_2, \ldots, a_n$.

翻译中…

The array $b$ is called to be a subsequence of $a$ if it is possible to remove some elements from $a$ to get $b$.

翻译中…

Array $b_1, b_2, \ldots, b_k$ is called to be good if it is not empty and for every $i$ ($1 \le i \le k$) $b_i$ is divisible by $i$.

翻译中…

Find the number of good subsequences in $a$ modulo $10^9 + 7$.

翻译中…

Two subsequences are considered different if index sets of numbers included in them are different. That is, the values ​of the elements ​do not matter in the comparison of subsequences. In particular, the array $a$ has exactly $2^n - 1$ different subsequences (excluding an empty subsequence).

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Input

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The first line contains an integer $n$ ($1 \le n \le 100\,000$) — the length of the array $a$.

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The next line contains integers $a_1, a_2, \ldots, a_n$ ($1 \le a_i \le 10^6$).

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Output

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Print exactly one integer — the number of good subsequences taken modulo $10^9 + 7$.

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Note

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In the first example, all three non-empty possible subsequences are good: $\{1\}$, $\{1, 2\}$, $\{2\}$

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In the second example, the possible good subsequences are: $\{2\}$, $\{2, 2\}$, $\{2, 22\}$, $\{2, 14\}$, $\{2\}$, $\{2, 22\}$, $\{2, 14\}$, $\{1\}$, $\{1, 22\}$, $\{1, 14\}$, $\{22\}$, $\{22, 14\}$, $\{14\}$.

翻译中…

Note, that some subsequences are listed more than once, since they occur in the original array multiple times.

翻译中…

样例

Input #1
2
1 2
Output #1
3
InputCopy OutputCopy
Input #2
5
2 2 1 22 14
Output #2
13
InputCopy OutputCopy
题目信息
题号
1061C
时间限制
3 s
内存限制
256 MB
标签
数据结构
动态规划
模拟
数学
数论

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