n,k = map(int,input().split())
a = list(map(int,input().split()))
result = 0
for i in range(n):
s = sum(a[i : i + k])
l = k
result = max(result, s / l)
for j in range(i + k, min(n, i + 2 * k)):
s += a[j]
l += 1
result = max(result, s / l)
print(result)#include <iostream>
#include <vector>
#include<iomanip>
using namespace std;
int main() {
int n,x,k;
cin>>n;
cin>>k;
vector<int> a;
vector<int> pre;
a.push_back(0);
pre.push_back(0);
for(int i = 0;i < n;i++){
cin>>x;
a.push_back(x);
}
for(int i = 1;i <= n;i++){
pre.push_back(a[i]+pre[i-1]);
}
double max = 0;
double sum=0;
long double average;
for(double i = k;i <= n;i++){
for(int j = 1;j <= n;j++){
if(j+i-1 > n) break;
sum = pre[j+i-1] - pre[j-1];
average = sum/i;
if(average > max) max = average;
}
}
cout<<setprecision(10);
cout<<max<<endl;
return 0;
}337A - Puzzles | 495A - Digital Counter |
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