#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int t = 1;
  while (t--) {
    int n = 0, m = 0, k = 0, i = 0, j = 0, p = 0, q = 0, x = 0, y = 0, z = 0,
        ans = 0, cnt = 0;
    string s;
    bool flag = false;
    cin >> n >> m;
    int a[n];
    map<int, int> frq;
    for (i = 0; i < n; i++) {
      cin >> a[i];
      if (frq.find(a[i]) == frq.end())
        frq[a[i]] = 1;
      else
        frq[a[i]]++;
    }
    vector<int> v;
    for (auto u : frq) {
      if (u.second >= u.first) v.push_back(u.first);
    }
    sort(v.begin(), v.end());
    k = v.size();
    int dp[k][n + 1];
    memset(dp, 0, sizeof(dp));
    for (j = 1; j <= n; j++) {
      for (i = 0; i < k; i++) dp[i][j] = dp[i][j - 1];
      for (i = 0; i < k; i++) {
        if (a[j - 1] == v[i]) {
          dp[i][j]++;
          break;
        }
      }
    }
    while (m--) {
      cnt = 0;
      cin >> p >> q;
      for (i = 0; i < k; i++) {
        y = dp[i][q] - dp[i][p - 1];
        if (y == v[i]) cnt++;
      }
      cout << cnt << endl;
    }
  }
  return 0;
}
