题目描述
Problem Statement
You are given $non-zero integers x_1, \ldots, x_N.$ Find the minimum and maximum values of $\dfrac{x_i+x_j+x_k}{x_ix_jx_k}$ for integers i, j, k such that $1\leq i < j < k\leq N$.
Input
The input is given from Standard Input in the following format:
N
$x_1 \ldots x_N$
Output
Print the minimum value of $\dfrac{x_i+x_j+x_k}{x_ix_jx_k}$ in the first line and the maximum value in the second line.
Your output will be considered correct when the absolute or relative error is at most 10^{-12}.
Constraints
- $3\leq N\leq 2\times 10^5$
- -$10^6\leq x_i \leq 10^6$
- $x_i\neq 0$
Sample Input 1
4
-2 -4 4 5
Sample Output 1
-0.175000000000000
-0.025000000000000
$\dfrac{x_i+x_j+x_k}{x_ix_jx_k}$ can take the following four values.
- (i,j,k) = (1,2,3): $\dfrac{(-2) + (-4) + 4}{(-2)\cdot (-4)\cdot 4} = -\dfrac{1}{16}$.
- (i,j,k) = (1,2,4): $\dfrac{(-2) + (-4) + 5}{(-2)\cdot (-4)\cdot 5} = -\dfrac{1}{40}$.
- (i,j,k) = (1,3,4): $\dfrac{(-2) + 4 + 5}{(-2)\cdot 4\cdot 5} = -\dfrac{7}{40}$.
- (i,j,k) = (2,3,4): $\dfrac{(-4) + 4 + 5}{(-4)\cdot 4\cdot 5} = -\dfrac{1}{16}$.
Among them, the minimum is -$\dfrac{7}{40}$, and the maximum is -$\dfrac{1}{40}$.
Sample Input 2
4
1 1 1 1
Sample Output 2
3.000000000000000
3.000000000000000
Sample Input 3
5
1 2 3 4 5
Sample Output 3
0.200000000000000
1.000000000000000
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分