//
// Created by ronal on 2/11/2023.
// Problem description link.
// https://practice.geeksforgeeks.org/problems/reverse-squared-sum/0
//
#include <iostream>
#include <vector>
using namespace std;
void inverter(vector<int> &V){
int start = 0;
int end = V.size() - 1;
while(start < end){
int tmp = V[start];
V[start] = V[end];
V[end] = tmp;
start++;
end--;
}
}
int SumReverse(vector<int> V){
int sum = 0;
int square = 0;
for(int i = 0; i < V.size(); i++){
square = V[i]*V[i];
if( i % 2 == 0){
sum += square;
}else{
sum -= square;
}
}
return sum;
}
int main() {
vector<int> V;
int tests, size, value;
cin >> tests;
for(int i = 0; i < tests; i++){
cin >> size;
for(int j = 0; j < size; j++){
cin >> value;
V.push_back(value);
}
inverter(V);
cout << SumReverse(V) << "\n";
V.clear();
}
return 0;
}