#include <iostream>
#include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <cstdlib>
#include <algorithm>
#include <vector>
#include <map>
#include <stack>
#include <queue>
#include <set>
#define m_p make_pair
#define p_b push_bakc
#define fi first
#define se second
#define LL long long
using namespace std;
const int maxn = 100010;
LL a[maxn];
LL l[maxn],r[maxn];
int main()
{
    //freopen("input.txt","r",stdin);
    //freopen("output.txt","w",stdout);
    int tt; scanf("%d",&tt);
    while(tt--)
    {
        int n;
        scanf("%d",&n);
        for (int i=1; i<=n; i++)
            scanf("%I64d",&a[i]);
        LL Max=abs(a[1]-a[2]);
        memset(l,0,sizeof(l));
        memset(r,0,sizeof(r));
        for (int i=2; i<n; i++)
        {
            l[i+1]=Max;
            Max=max(Max,abs(a[i]-a[i+1]));
        }
        Max=abs(a[n]-a[n-1]);
        for (int i=n-1; i>1; i--)
        {
            r[i-1]=Max;
            Max=max(Max,abs(a[i]-a[i-1]));
        }

        LL sum=r[1]+l[n];
        for (int i=2; i<=n-1; i++)
            sum+=max(abs(a[i-1]-a[i+1]),max(l[i],r[i]));
        printf("%I64d\n",sum);
    }

    return 0;
}