[传送门](https://www.patest.cn/contests/pat-b-practise/1056)
#include<iostream>
using namespace std;
int main(){
int N;
int num;
int sum=0;
cin>>N;
for(int i=0;i<N;i++){
cin>>num;
sum+=(N-1)*10*num+(N-1)*num;
}
cout<<sum<<endl;
}