#include <stdio.h>
#include <atcoder/all>
#include <bits/stdc++.h>
using namespace std;
using namespace atcoder;
using mint = modint998244353;
#define rep(i,n) for (int i = 0; i < (n); ++i)
#define Inf32 1000000005
#define Inf64 4000000000000000001LL

int main(){
	
	int _t;
	cin>>_t;
	rep(_,_t){
		int n;
		cin>>n;
		vector<int> a(n);
		rep(i,n)cin>>a[i];
		vector dp(2,vector<long long>(3,-Inf64));
		dp[0][0] = a[0];
		dp[1][0] = -a[0];
		for(int i=1;i<n;i++){
			vector ndp(2,vector<long long>(3,-Inf64));
			rep(j,2){
				rep(k,3){
					rep(l,2){
						int nj = l;
						int nk = k;
						if(j!=l)nk++;
						if(nk==3)continue;
						long long nv = dp[j][k];
						if(l==0)nv += a[i];
						else nv -= a[i];
						ndp[nj][nk] = max(ndp[nj][nk],nv);
					}
				}
			}
			swap(dp,ndp);
		}
		long long ans = 0;
		rep(i,2){
			rep(j,3){
				ans = max(ans,dp[i][j]);
			}
		}
		cout<<ans<<endl;
	}
	
	return 0;
}