#include <bits/stdc++.h>
using namespace std;
int ans = 0, n;
int arr[110003];
int couqnt[110003];
int res[110003];
void add(int x) {
  if (arr[x] > n) {
    return;
  }
  if (couqnt[arr[x]] == arr[x]) {
    ans--;
  }
  couqnt[arr[x]]++;
  if (couqnt[arr[x]] == arr[x]) {
    ans++;
  }
}
void remove(int x) {
  if (arr[x] > n) {
    return;
  }
  if (couqnt[arr[x]] == (arr[x])) {
    ans--;
  }
  couqnt[arr[x]]--;
  if (couqnt[arr[x]] == (arr[x])) {
    ans++;
  }
}
int main() {
  int st, en, q;
  int buc = 316;
  cin >> n >> q;
  for (int i = 0; i < n; i++) {
    cin >> arr[i];
  }
  vector<pair<pair<int, int>, pair<int, int> > > v(q);
  for (int i = 0; i < q; i++) {
    cin >> st;
    st--;
    cin >> en;
    v[i] = make_pair(make_pair(st / buc, en), make_pair(st, i));
  }
  sort(v.begin(), v.end());
  int curst = 0;
  int curen = 0;
  for (int i = 0; i < q; i++) {
    st = v[i].second.first;
    en = v[i].first.second;
    int id = v[i].second.second;
    while (curst > st) {
      curst--;
      add(curst);
    }
    while (curen < en) {
      add(curen);
      curen++;
    }
    while (curst < st) {
      remove(curst);
      curst++;
    }
    while (curen > en) {
      curen--;
      remove(curen);
    }
    res[id] = ans;
  }
  for (int i = 0; i < q; i++) {
    printf("%d\n", res[i]);
  }
}
