#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define ll long long
#define pll pair<ll, ll>
#define pii pair<int,int>
#define pb push_back
#define F first
#define S second
#define mod 1000000007
#define maxn 1000005
#define inf 1e18
#define boost ios::sync_with_stdio(false);cin.tie(0)
#define fr freopen("source.txt","r",stdin),freopen("output.txt","w",stdout)
#define SET(a,b) memset(a,b,sizeof(a))
ll a[maxn],dp[maxn][2];
ll n;
ll go(ll i,ll j){
    if(i==(n-1)) return 0;
    ll &ans=dp[i][j];
    ans=0;
    if(i==0){
        ans=max(ans,abs(a[i]-1)+go(i+1,1));
        ans=max(ans,abs(a[i]-a[i+1])+go(i+1,0));
        ans=max(ans,abs(1-a[i+1])+go(i+1,0));
    }
    else if(j==0){
        ans=max(ans,abs(a[i]-1)+go(i+1,1));
        ans=max(ans,abs(a[i]-a[i+1])+go(i+1,0));
    }
    else{
        ans=max(ans,go(i+1,1));
        ans=max(ans,abs(1-a[i+1])+go(i+1,0));
    }
    return ans;
}
int main()
{
    boost;
    ll i,j,x,t;
    cin>>t;
    while(t--){
        cin>>n;
        for(i=0;i<n;i++)cin>>a[i];
        SET(dp,-1);
        cout<<go(0,0)<<"\n";
    }
}