AtCoder Grand Contest 047
A
Integer Product
AtCoder
⌀ 1592
原题
←B →
翻译中…

Problem Statement

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You are given $N$ real values $A_1, A_2, \ldots, A_N$. Compute the number of pairs of indices $(i, j)$ such that $i < j$ and the product $A_i \cdot A_j$ is integer.

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Constraints

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  • $2 \leq N \leq 200\,000$
  • $0 < A_i < 10^4$
  • $A_i$ is given with at most 9 digits after the decimal.
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Input

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Input is given from Standard Input in the following format.

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N
A_1
A_2
\vdots
A_N

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Output

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Print the number of pairs with integer product $A_i \cdot A_j$ (and $i < j$).

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样例

Input #1
5
7.5
2.4
17.000000001
17
16.000000000
Output #1
3
There are 3 pairs with integer product: - $7.5 \cdot 2.4 = 18$ - $7.5 \cdot 16 = 120$ - $17 \cdot 16 = 272$
Input #2
11
0.9
1
1
1.25
2.30000
5
70
0.000000001
9999.999999999
0.999999999
1.000000001
Output #2
8
题目信息
题号
agc047_a
时间限制
2 s
内存限制
1024 MB

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