//#include <bits\stdc++.h>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <cstdlib>
#include <vector>
#include <stack>
#include <queue>
#include <map>
#include <set>
#include <ctime>
#include <cmath>
#include <algorithm>

#define sqr(x) (x)*(x)
#define lson (p<<1)
#define rson (lson | 1)
#define eps 1e-10
#define pii pair<int,int>
#define mk(x,y) make_pair(x,y)

using namespace std;
typedef long long llg;
const int N = 1e5+10;
llg a[N];
struct Node
{
    llg l,r;
}f[N];
bool cmp(Node x,Node y)
{
    if(x.l == y.l) return x.r > y.r;
    return x.l < y.l;
}
int main()
{
    int n,cas;
    llg l,r;
    scanf("%d",&cas);
    while(cas--)
    {
        scanf("%d%I64d%I64d",&n,&l,&r);
        for(int i=0;i<n;i++)
        {
            scanf("%I64d",&a[i]);
        }
        sort(a,a+n);
        for(int i=1;i<n;i++)
        {
            f[i-1].l = a[i] - a[i-1] + 1LL;
            f[i-1].r = a[i] + a[i-1] - 1LL;
            f[i-1].r = min(r,f[i-1].r);
        }
        sort(f,f+n-1,cmp);
        llg ans = 0,x=l;
        for(int i=0;i<n-1;i++)
        {
            if(f[i].l>f[i].r) continue;
            if(f[i].r>=x)
            {
                ans += f[i].r - max(x,f[i].l) + 1LL;
                x = f[i].r+1LL;
            }
        }
        ans = (r-l+1LL) - ans;
        cout<<ans<<endl;
    }
    return 0;
}