C :

#include<stdio.h>
int a[1000001];
main() {
	int j,i,n,m;
	scanf("%d %d",&n,&m);
	for(i = 0; i < n; i++) {
		scanf("%d",&a[i]);
	}
	double avg = 0;
	for(i = 0; i <= n - m; i++) {
		//求m个小时的最大值
		double s = 0;
		for(j = i; j < i + m ; j++) {
			s = s + a[j];
		}
		s = s / m;

		if(s > avg) {
			avg = s;
		}

	}

	printf("%.2f",avg);
}

C++ :

#include <bits/stdc++.h>
using namespace std;
int a[110];
int main(){
	int n,m;
	cin>>n>>m;
	for(int i=0;i<n;i++)
	{
		cin>>a[i];
	}
	float max=0;
	int s;
	for(int i=0;i<n-m+1;i++)
	{
		s=0;
		for(int j=i;j<m+i;j++)
		{
			s+=a[j];
		}
		if(s>max)
		{
			max=s;
		}
	}
	cout<<fixed<<setprecision(2)<<max/m<<endl;
	return 0;
}

Pascal :

var m,n,max,num,i:longint;
    sum:array[0..1000000] of longint;
begin
 read(n,m);

 for i:=1 to n do begin
  read(num);
  sum[i]:=sum[i-1]+num;
 end;

 for i:=m to n do if sum[i]-sum[i-m]>max then max:=sum[i]-sum[i-m];

 writeln(max/m:0:2);
end.

Java :

import java.text.DecimalFormat;
import java.util.Scanner;
public class Main{
	public static void main(String[] args) {
		// TODO Auto-generated method stub
		Scanner scanner =new Scanner(System.in);
		String str=scanner.nextLine();
		String[] array=str.split(" ");
		int N=Integer.valueOf(array[0]);
		int M=Integer.valueOf(array[1]);
		String speedStr=scanner.nextLine();
		String[] speedarray=speedStr.split(" ");
		int sumMax=0;
		for(int i=0;i<(N-M+1);i++){
			int sum=0;
			for(int j=0;j<M;j++){
				sum=sum+Integer.valueOf(speedarray[j+i]);
			}
			if(sum>=sumMax){
				sumMax=sum;
			}
		}
		float avg=(float)sumMax/M;
		DecimalFormat df = new DecimalFormat("#.00");
		 System.out.println(df.format(avg));
	}
}

Python :

n,m = map(int,input().split())
myList = list(map(int,input().split()))
max = 0
for i in range(0,n - m + 1):
     s = 0
     for j in range(i,i + m):
          s = s + myList[j]
     if s / m > max:
          max = s / m
print("%.2f"%(max))