继续不开ll 见祖宗

#include<iostream>
#include<cmath>
#include<algorithm>
using namespace std;
using ll = long long;
const int N = 1e5+10;
ll a[N];
int main()
{
    int n;cin>>n;
    ll sum = 0;
    for(int i = 1;i <= n;i++)cin>>a[i];
    sort(a+1,a+1+n);
    //for(int i = 1;i <= n;i++)cout<<a[i]<<" ";
    for(int i = 1;i < n;i++)
    {
        a[i] += a[i-1];
        sum += a[i];
    }
    cout<<sum<<"\n";
    return 0; 
}