#define _CRT_SECURE_NO_WARNINGS
#define _SILENCE_CXX17_C_HEADER_DEPRECATION_WARNING
#include <bits/stdc++.h>
using namespace std;
#define CRP(t, x) const t &x
#define OPL(t, x) bool operator<(CRP(t, x)) const
#define FIL(x, v) memset(x, v, sizeof(x))
#define CLR(x) FIL(x, 0)
#define NE1(x) FIL(x, -1)
#define INF(x) FIL(x, 0x3f)
typedef long long ll, i64;
const int N = 2e6 + 50, inf = 0x3f3f3f3f;
int a[N], b[N], idx, rt[N], stub[N << 1];
struct node
{
    int ch[2], sz;
} T[N * 21];
void insert(int y, int &x, int l, int r, int p)
{
    T[x = ++idx] = T[y];
    T[x].sz++;
    if (l == r - 1) return;
    int m = (l + r) >> 1;
    p < m ?
        insert(T[y].ch[0], T[x].ch[0], l, m, p) :
        insert(T[y].ch[1], T[x].ch[1], m, r, p);
}
int query(int nl, int nr, int l, int r, int k)
{
    if (l == r - 1) return l;
    int d = T[T[nr].ch[0]].sz - T[T[nl].ch[0]].sz, m = (l + r) >> 1;
    return d > k ?
               query(T[nl].ch[0], T[nr].ch[0], l, m, k) :
               query(T[nl].ch[1], T[nr].ch[1], m, r, k - d);
}
int rnk(int nl, int nr, int l, int r, int v)
{
    if (l == r - 1) return 0;
    int m = (l + r) >> 1;
    return v < m ? rnk(T[nl].ch[0], T[nr].ch[0], l, m, v) :
                   T[T[nr].ch[0]].sz + rnk(T[nl].ch[1], T[nr].ch[1], m, r, v);
    return 0;
}
int main()
{
#ifdef _MSC_VER
    freopen(R"(E:\UserData\Desktop\K-th Closest Distance\14162.in)", "r", stdin);
#endif // _MSC_VER
    /*int q;
    scanf("%d%d", &n, &q);
    for (int i = 1; i <= n; i++) scanf("%d", a + i);
    memcpy(b, a + 1, n << 2);
    std::sort(b, b + n);
    int m = int(std::unique(b, b + n) - b);
    for (int i = 1; i <= n; i++)
        a[i] = int(std::lower_bound(b, b + m, a[i]) - b);
    for (int i = 1; i <= n; i++) insert(rt[i - 1], rt[i], 0, m, a[i]);
    while (q--)
    {
        int l, r, k;
        scanf("%d%d%d", &l, &r, &k);
        printf("%d\n", b[query(rt[l - 1], rt[r], 0, m, k)]);
    }*/
    int Tt, n, m, L, R, P, K, X;
    scanf("%d", &Tt);
    while (Tt--)
    {
        scanf("%d%d", &n, &m);
        CLR(rt), CLR(T), idx = X = 0;
        for (int i = 1; i <= n; i++) scanf("%d", a + i);
        a[++n] = inf;
        memcpy(b, a + 1, sizeof(*a) * n);
        std::sort(b, b + n);
        //int bn = int(std::unique(b, b + n) - b);
        for (int i = 1; i <= n; i++)
            a[i] = lower_bound(b, b + n, a[i]) - b;
        for (int i = 1; i <= n; i++) insert(rt[i - 1], rt[i], 0, n, a[i]);
        /*for (int i = 0; i < n - 1; i++)
            printf("%d ", b[query(rt[0], rt[n], 0, n, i)]);
        putchar('\n');
        for (int i = 1; i < n; i++)
            printf("%d ", rnk(rt[0], rt[n], 0, n, a[i]));
        printf("%d ", rnk(rt[0], rt[n], 0, n, a[n]));
        putchar('\n');*/
        while (m--)
        {
            scanf("%d%d%d%d", &L, &R, &P, &K);
            L ^= X, R ^= X, P ^= X, K ^= X;
            /*
            int ansL = 0, ansR = 1e6, ansM, Lb, Rb;
            while (ansL < ansR - 1)
            {
                ansM = (ansL + ansR) >> 1;
                Lb = rnk(rt[L - 1], rt[R], 0, n, lower_bound(b, b + n, P - ansM) - b);
                Rb = rnk(rt[L - 1], rt[R], 0, n, lower_bound(b, b + n, P + ansM) - b);
                if (Rb - Lb + 1 > K)
                    ansR = ansM;
                else
                    ansL = ansM;
            }
            X = ansL;
            Lb = rnk(rt[L - 1], rt[R], 0, n, lower_bound(b, b + n, P - X) - b);
            Rb = rnk(rt[L - 1], rt[R], 0, n, lower_bound(b, b + n, P + X) - b);
            if (Rb - Lb + 1 < K) X++;*/
            static int arr[400];
            int cnt = 0;
            int rkP = rnk(rt[L - 1], rt[R], 0, n, lower_bound(b, b + n, P) - b);
            int fr = max(rkP - 169, 0), to = min(rkP + 169, R - L);
            for (int i = fr; i <= to; i++)
                arr[cnt++] = abs(P - b[query(rt[L - 1], rt[R], 0, n, i)]);
            sort(arr, arr + cnt);
            printf("%d\n", X = arr[K - 1]);
            cnt++;
        }
    }
    return 0;
}