#include <bits/stdc++.h>
using namespace std;
const int N = 100009;
int sol, qs[N], qe[N], sorted[N], ans[N], a[N], s, e;
unordered_map<int, int> freq;
void add(int el) {
  sol -= !(freq[el] ^ el);
  freq[el]++;
  sol += !(freq[el] ^ el);
}
void remove(int el) {
  sol -= !(freq[el] ^ el);
  freq[el]--;
  sol += !(freq[el] ^ el);
}
void mo(int idx) {
  while (s > qs[idx]) add(a[--s]);
  while (e <= qe[idx]) add(a[e++]);
  while (s < qs[idx]) remove(a[s++]);
  while (e > qe[idx] + 1) remove(a[--e]);
  ans[idx] = sol;
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  int n, m;
  cin >> n >> m;
  for (int i = 0; i < n; i++) cin >> a[i];
  for (int i = 0; i < m; i++) {
    cin >> qs[i] >> qe[i];
    qs[i]--, qe[i]--;
    sorted[i] = i;
  }
  int sq = sqrt(n);
  sort(sorted, sorted + m, [sq](int i, int j) {
    return make_pair(qs[i] / sq, qe[i]) < make_pair(qs[j] / sq, qe[j]);
  });
  for (int i = 0; i < m; i++) mo(sorted[i]);
  for (int i = 0; i < m; i++) cout << ans[i] << "\n";
}
