1 #include<cstdio> 2 #include<cstring> 3 #include<algorithm> 4 #include<iostream> 5 #include<cmath> 6 #include<ctime> 7 #include<cctype> 8 using namespace std; 9 const int MAXN=100000+10;10 inline int get_num(){11     int res=0,f=1;char ch=getchar();12     while(!isdigit(ch)){if(ch == ‘-‘) f=-1;ch=getchar();}13     while(isdigit(ch)){14         res=(res<<1)+(res<<3)+(ch^0x30);15         ch=getchar();16     }17     return res*f;18 }19 int N,k;20 int sum[MAXN];21 int que[MAXN];22 double getk(int l,int r){23     return (sum[r]-sum[l-1])*1.0/(r-l+1);24 }25 26 int main(){27     scanf("%d %d",&N,&k);28     for(int i=1;i<=N;i++){29         sum[i]=sum[i-1]+get_num();    30     }31     double res=-1e15;32     int hd=1,tl=0;33     for(int i=k;i<=N;i++){34         while(hd <= tl && que[hd] > i-k) hd++;35         while(hd <= tl && getk(que[tl],i) < getk(i-k+1,i)) tl--;36         que[++tl]=i-k+1;37         res=max(res,getk(que[hd],i));38     }39     printf("%d\n",(int)(res*1000));40     return(0);41 }