https://codeforces.me/problemset/problem/1557/A

void solve(){ ll n;cin>>n; vll arr(n); FOR(i,0,n)cin>>arr[i]; double m=*max_element(all(arr)); double sum = accumulate(all(arr),0); sum=sum-m; double avg = sum/(n-1);

cout<<fixed<<setprecision(10)<<m+avg<<endl;

}