zoj 2091 Mean of Subsequence

#include<iostream>#include<cstdio>using namespace std;#define Max 10005double a[Max],b[Max];int main(){    int i,n;    while(cin>>n)    {        for(i=0;i<n;i++) cin>>a[i];        double sum=0.0;        for(i=n-1;i>=0;i--)        { sum+=a[i]; b[i]=sum/(n-i);        }        double max=0;        for(i=0;i<n;i++) if(max<b[i]) max=b[i];        printf("%.6fn",max);    }    return 0;}