Prosjek

You are given an array of $N$ integers. Find a consecutive subsequence of numbers of the length at least $K$ that has the maximal possible average.

Input

The first line of input contains two integers $N$ ($1 \leq N \leq 3 \cdot 10^5$) and $K$ ($1 \leq K \leq N$). The second line of input contains $N$ integers $a_ i$ ($1 \leq a_ i \leq 10^6$).

Output

The first and only line of output must contain the maximal possible average. An absolute deviation of $\pm 0.001$ from the official solution is permitted.

Sample Input 1 Sample Output 1
4 1
1 2 3 4
4.000000
Sample Input 2 Sample Output 2
4 2
2 4 3 4
3.666666
Sample Input 3 Sample Output 3
6 3
7 1 2 1 3 6
3.333333