#include <bits/stdc++.h>
using namespace std;
const long long N = 200005;
long long cnt[N], A[N], ans[N];
long long BS;
vector<pair<long long, pair<long long, long long> > > qu;
long long cur_ans = 0;
bool comp(pair<long long, pair<long long, long long> > &a,
          pair<long long, pair<long long, long long> > &b) {
  if (a.first / BS != b.first / BS)
    return a.first / BS < b.first / BS;
  else
    return a.second.first < b.second.first;
}
void add(long long x) {
  if (cnt[x] == x) cur_ans--;
  cnt[x]++;
  if (cnt[x] == x) cur_ans++;
}
void sub(long long x) {
  if (cnt[x] == x) cur_ans--;
  cnt[x]--;
  if (cnt[x] == x) cur_ans++;
}
void solve() {
  long long n, m;
  cin >> n >> m;
  for (__typeof((n)) i = (1); i <= (n); i++) {
    cin >> A[i];
    if (A[i] > 100000) A[i] = 100001;
  }
  qu.resize(m);
  BS = sqrt(n);
  for (__typeof((m - 1)) i = (0); i <= (m - 1); i++) {
    cin >> qu[i].first >> qu[i].second.first;
    qu[i].second.second = i;
  }
  sort((qu).begin(), (qu).end(), comp);
  long long L = 0;
  long long R = -1;
  for (long long i = 0; i < m; i++) {
    long long l = qu[i].first;
    long long r = qu[i].second.first;
    long long id = qu[i].second.second;
    while (R < r) {
      R++;
      add(A[R]);
    }
    while (R > r) {
      sub(A[R]);
      R--;
    }
    while (L > l) {
      L--;
      add(A[L]);
    }
    while (L < l) {
      sub(A[L]);
      L++;
    }
    ans[id] = cur_ans;
  }
  for (long long i = 0; i < m; i++) cout << ans[i] << '\n';
}
signed main() {
  long long t;
  ios_base::sync_with_stdio(false);
  t = 1;
  while (t--) solve();
  return 0;
}
