The Little Elephant loves playing with arrays. He has array a, consisting of n positive integers, indexed from 1 to n. Let's denote the number with index i as ai. 

Additionally the Little Elephant has m queries to the array, each query is characterised by a pair of integers lj and rj (1 ≤ lj ≤ rj ≤ n). For each query lj, rj the Little Elephant has to count, how many numbers x exist, such that number x occurs exactly x times among numbers alj, alj + 1, ..., arj.

Help the Little Elephant to count the answers to all queries.

Input

The first line contains two space-separated integers n and m (1 ≤ n, m ≤ 105) — the size of array a and the number of queries to it. The next line contains n space-separated positive integers a1, a2, ..., an (1 ≤ ai ≤ 109). Next m lines contain descriptions of queries, one per line. The j-th of these lines contains the description of the j-th query as two space-separated integers lj and rj (1 ≤ lj ≤ rj ≤ n).

Output

In m lines print m integers — the answers to the queries. The j-th line should contain the answer to the j-th query.

Examples

Input

7 2
3 1 2 2 3 3 7
1 7
3 4


Output

3
1
#include <bits/stdc++.h>
using namespace std;
const int inf = 1e9 + 5;
const double eps = 0;
const int ms = 0;
const int md = 0;
const int N = 1e5 + 5;
int n, m, block;
unordered_map<int, int> mm;
int a[N];
pair<pair<int, int>, int> query[N];
bool cmp(pair<pair<int, int>, int> &a, pair<pair<int, int>, int> &b) {
  return (a.first.first / block < b.first.first / block) ||
         (a.first.first / block == b.first.first / block &&
          a.first.second > b.first.second);
}
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cin >> n >> m;
  block = sqrt(n);
  for (int i = 0; i <= n - 1; i++) cin >> a[i];
  for (int i = 0; i <= m - 1; i++) {
    cin >> query[i].first.first >> query[i].first.second;
    --query[i].first.first, --query[i].first.second;
    query[i].second = i;
  }
  sort(query, query + m, cmp);
  int res = 0;
  int l = query[0].first.first, r = query[0].first.second;
  for (int i = l; i <= r; i++) {
    ++mm[a[i]];
    if (mm[a[i]] == a[i])
      ++res;
    else if (mm[a[i]] == a[i] + 1)
      --res;
  }
  vector<long long> rr(m);
  rr[query[0].second] = res;
  for (int i = 1; i <= m - 1; i++) {
    if (query[i].first.first < l) {
      for (int j = l - 1; j >= query[i].first.first; j--) {
        ++mm[a[j]];
        if (mm[a[j]] == a[j])
          ++res;
        else if (mm[a[j]] == a[j] + 1)
          --res;
      }
    } else {
      for (int j = l; j <= query[i].first.first - 1; j++) {
        --mm[a[j]];
        if (mm[a[j]] == a[j])
          ++res;
        else if (mm[a[j]] == a[j] - 1)
          --res;
      }
    }
    if (query[i].first.second < r) {
      for (int j = r; j >= query[i].first.second + 1; j--) {
        --mm[a[j]];
        if (mm[a[j]] == a[j])
          ++res;
        else if (mm[a[j]] == a[j] - 1)
          --res;
      }
    } else {
      for (int j = r + 1; j <= query[i].first.second; j++) {
        ++mm[a[j]];
        if (mm[a[j]] == a[j])
          ++res;
        else if (mm[a[j]] == a[j] + 1)
          --res;
      }
    }
    l = query[i].first.first, r = query[i].first.second;
    rr[query[i].second] = res;
  }
  for (int u : rr) cout << u << "\n";
  return 0;
}
