//editor: Jan Tang
//problem:
#include <iostream>
#include <cstdio>
#include <string>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <map>
#include <stack>
#include <queue>
#include <set>
#include <cstdlib>
using namespace std;
#define set0(a) memset(a,0,sizeof(a));
#define CIN(a,n) for(int i=1;i<=n;i++) cin>>a[i];
typedef long long ll;
typedef unsigned long long ull;
const int Mod = 1e9+7;
const int maxn = 100005;
const int inf = 0x3f3f3f3f;
int m,n, a[maxn], b[maxn], pre[maxn], aft[maxn];
/*==============================head==========================*/
int main(){
    int T; cin >> T; 
    while(T -- > 0){
        scanf("%d", &n);
        set0(b);set0(pre);set0(aft);set0(a);
        int tmp = 0, maxn = -1;
        for(int i =1; i <=n; i++){
            scanf("%d", &a[i]);
            if(i >= 2)
                b[i-1] = abs(a[i] - a[i-1]);
        }
        for(int i = 2; i<= n ; i++){
            pre[i] = max(b[i-1], pre[i-1]);
        }
        for(int i = n-1; i >=1; i--){
            aft[i] = max(b[i], aft[i+1]);
        }
        ll ans = 0;
        for(int i = 1;i <=n; i++){
        //    cout<<i<<"  "<<pre[i]<< "  "<<aft[i]<<endl;
            if(i >= 2 && i <= n-1)
                ans += max( max(aft[i+1], pre[i-1]), abs(a[i+1]-a[i-1]));
            else ans += max(aft[i+1], pre[i-1]);
        }
        printf("%lld\n",ans);
    }
    return 0;
}