#include <bits/stdc++.h>
using ll = long long;
using namespace std;
#define rep(i, s, t) for (ll i = s; i < (ll)(t); i++)
#define rrep(i, s, t) for (ll i = (ll)(t) - 1; i >= (ll)(s); i--)
#define all(x) begin(x), end(x)
#define rall(x) rbegin(x), rend(x)

template <typename T> bool chmin(T& x, T y) {
	return x > y ? (x = y, true) : false;
}
template <typename T> bool chmax(T& x, T y) {
	return x < y ? (x = y, true) : false;
}

struct io_setup {
	io_setup() {
		ios::sync_with_stdio(false);
		std::cin.tie(nullptr);
		cout << fixed << setprecision(15);
	}
} io_setup;

#include <atcoder/all>

void solve() {
	int n;
	cin>>n;
	vector<ll> a(n);
	rep(i,0,n) cin>>a[i];
	vector<ll> dp(6,0);
	rep(i,0,n){
		vector<ll> ndp(6,0);
		ndp[0]=dp[0]+a[i];
		ndp[1]=dp[1]-a[i];
		ndp[2]=max({dp[0],dp[1],dp[2]})+a[i];
		ndp[3]=max({dp[0],dp[1],dp[3]})-a[i];
		ndp[4]=max({dp[2],dp[3],dp[4]})+a[i];
		ndp[5]=max({dp[2],dp[3],dp[5]})-a[i];
		swap(dp,ndp);
	}
	cout<<max(dp[4],dp[5])<<"\n";
}

int main() {
	int t = 1;
	cin >> t;
	while (t--) solve();
}