#include <cstdio>

#include <cmath>

#include <cstring>

#include <iostream>

#include <algorithm>

#include <queue>

#include <vector>

#include <map>



using namespace std;



typedef long long LL;


int T;
LL n,l,r,a[100005];
LL ans;
struct Node
{
    LL l,r;
}dq,f[100005];
bool cmp(Node a,Node b)
{
    if (a.l!=b.l) return a.l<b.l;
    return a.r<b.r;
}
LL work(Node a,LL l,LL r)
{
    if (a.r<l) return 0;
    if (a.l>r) return 0;
    l=max(a.l,l);
    r=min(a.r,r);
    return r-l+1;
}

int main()

{
    scanf("%d",&T);
    while (T--)
    {
        scanf("%I64d%I64d%I64d",&n,&l,&r);
        for (int i=1;i<=n;++i) scanf("%I64d",&a[i]);
        sort(a+1,a+n+1);
        for (int i=2;i<=n;++i)
        {
            f[i-1].l=a[i]-a[i-1]+1;
            f[i-1].r=a[i]+a[i-1]-1;
        }
        sort(f+1,f+n-1+1,cmp);
        int i=1;
        ans=0;
        while (i<=n-1)
        {
            dq=f[i];
            int j=i+1;
            while (j<=n-1&&f[j].l<=dq.r)
            {
                dq.r=max(f[j].r,dq.r);
                j++;
            }        
            ans+=work(dq,l,r);
            i=j;        
        }
        ans=r-l+1-ans;
        printf("%I64d\n",ans);
    }

    return 0;

}