#include <bits/stdc++.h>
#define fi first
#define se second
#define rep(i,s,n) for (int i = (s); i < (n); ++i)
#define rrep(i,n,g) for (int i = (n)-1; i >= (g); --i)
#define all(a) a.begin(),a.end()
#define rall(a) a.rbegin(),a.rend()
#define len(x) (int)(x).size()
#define dup(x,y) (((x)+(y)-1)/(y))
#define pb push_back
#define eb emplace_back
#define Field(T) vector<vector<T>>
using namespace std;
using ll = long long;
using ull = unsigned long long;
template<typename T> using pq = priority_queue<T,vector<T>,greater<T>>;
using P = pair<int,int>;
template<class T>bool chmax(T&a,T b){if(a<b){a=b;return 1;}return 0;}
template<class T>bool chmin(T&a,T b){if(b<a){a=b;return 1;}return 0;}

void solve() {
  int n;
  cin >> n;
  vector<int> a(n);
  rep(i,0,n) cin >> a[i];
  vector<ll> s(n+1);
  rep(i,0,n) s[i+1] = s[i] + a[i];
  ll v1 = abs(a[0])+a[1], v2 = abs(a[0])-a[1];
  ll ans = 0;
  rep(i,2,n) {
    ans = max(ans, max(v1, v2) + s[n]-s[i]);
    v1 = max(v1+a[i], abs(s[i])+a[i]);
    v2 = max(v2-a[i], abs(s[i])-a[i]);
  }
  cout << ans << endl;
}

int main() {
  int t;
  cin >> t;
  while(t--) solve();
  return 0;
}