Note.ms

#include <bits/stdc++.h>

using namespace std;

using Pii = pair<int, int>;

const int N = 2e5 + 5, inf = 1e9;

struct F {
  int l, r;
} x[N];

struct node {
  int x;
} tr[N * 4];

int t, n, q, a[N], ans[N];

stack<int> stk;

vector<Pii> v[N], que[N];

void build(int i, int l, int r) {
  if (l == r) {
    tr[i].x = inf;
    return ;
  }
  int mid = (l + r) >> 1;
  build(i * 2, l, mid);
  build(i * 2 + 1, mid + 1, r);
  tr[i].x = inf;
}

void modify(int i, int l, int r, int p, int x) {
  if (l == r) {
    tr[i].x = min(tr[i].x, x);
    return ;
  }
  int mid = (l + r) >> 1;
  if (mid >= p) {
    modify(i * 2, l, mid, p, x);
  }
  else modify(i * 2 + 1, mid + 1, r, p, x);
  tr[i].x = min(tr[i * 2].x, tr[i * 2 + 1].x);
}

int query(int i, int l, int r, int x, int y) {
  if (l > y || r < x) {
    return inf;
  }
  if (l >= x && r <= y) {
    return tr[i].x;
  }
  int mid = (l + r) >> 1;
  return min(query(i * 2, l, mid, x, y), query(i * 2 + 1, mid + 1, r, x, y));
}

void Solve() {
  cin >> n >> q;
  for (int i = 1; i <= n; i++) {
    cin >> a[i];
  }
  for (int i = 1; i <= n; i++) {
    while (!stk.empty() && a[i] < a[stk.top()]) {
      stk.pop();
    }
    if (stk.empty()) {
      x[i].l = 0;
    }
    else x[i].l = stk.top();
    stk.push(i);
  }
  while (!stk.empty()) {
    stk.pop();
  }
  for (int i = n; i >= 1; i--) {
    while (!stk.empty() && a[i] > a[stk.top()]) {
      stk.pop();
    }
    if (stk.empty()) {
      x[i].r = n + 1;
    }
    else x[i].r = stk.top();
    stk.push(i);
  }
  for (int i = 1; i <= n; i++) {
    if (!x[i].l || x[i].r == n + 1) {
      continue;
    }
    v[x[i].l].push_back({x[i].r, (x[i].r - x[i].l + 1) - 3});
  }
  for (int i = 1, l, r; i <= q; i++) {
    cin >> l >> r;
    que[l].push_back({r, i});
  }
  build(1, 1, n);
  for (int i = n; i >= 1; i--) {
    for (auto cur : v[i]) {
      modify(1, 1, n, cur.first, cur.second);
    }
    for (auto cur : que[i]) {
      int tmp = query(1, 1, n, i, cur.first);
      if (tmp == inf) {
        ans[cur.second] = -1;
      }
      else ans[cur.second] = (cur.first - i + 1) - tmp;
    }
  }
  for (int i = 1; i <= q; i++) {
    cout << ans[i] << "\n";
  }
  while (!stk.empty()) {
    stk.pop();
  }
  for (int i = 1; i <= n; i++) {
    v[i].clear();
    que[i].clear();
  }
}

int main() {
  // freopen("5.in", "r", stdin);
  // freopen("ans.out", "w", stdout);
  ios::sync_with_stdio(0);
  cin.tie(0);
  cin >> t;
  while (t--) {
    Solve();
  }
  return 0;
}

Note.ms/998244353