题目描述
An instructor may use curved score to grade a student’s performance. Assume a student’s original score is $x$ out of a total of $100$. One of the curving methods is to apply to $x$ the curving function $f(x) = 10\sqrt {x}$. The function may be applied $k \geq 0$ times. For better score readability, the result is rounded to the next integer and the final curved score is $y = \lceil f^k(x) \rceil$.
For example, if the curving function is applied $k = 3$ times to $x = 80$, it changes the score to\begin{align} f^3(80) & = f^2(f(80)) = f^2(89.4427) \ & = f(f(89.4427)) = f(94.5742) = 97.2492. \end{align}
So the curved score is $y = \lceil 97.2492 \rceil = 98$.
John wants to curve a student’s score $x$ using this method so that the curved score $y$ is between $y_{low}$ and $y_{high}$. How many times should he apply the curving function? In particular, what are the minimum and maximum choices of $k$, so that $y_{low} \leq y \leq y_{high}$?
-----Input-----
The input has a single line with three integers: $x$, $y_{low}$, and $y_{high}$ ($1 \leq x \leq y_{low} \leq y_{high} \leq 100$).
-----Output-----
Output the minimum and maximum possible choices of $k$. If the curving function can be applied an infinite number of times, output “inf” for the maximum. If there is no $k$ that meets the curving requirement, output a single word “impossible”.
-----Examples-----
Sample Input 1:
80 85 98
Sample Output 1:
1 3
Sample Input 2:
98 98 100
Sample Output 2:
0 inf
输入格式
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输出格式
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