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;
int block;
bool compare(tuple<int, int, int> x, tuple<int, int, int> y) {
  return make_pair(get<0>(x) / block, get<1>(x)) <
         make_pair(get<0>(y) / block, get<1>(y));
}
int sequence[100010];
unordered_map<int, int> arr;
int main() {
  int n, m;
  scanf("%d %d", &n, &m);
  block = (int)sqrt(n);
  for (int i = 0; i < n; i++) {
    scanf("%d", &sequence[i]);
    arr[sequence[i]] = 0;
  }
  int a, b;
  vector<tuple<int, int, int>> queries(m);
  vector<int> answers(m);
  for (int i = 0; i < m; i++) {
    scanf("%d %d", &a, &b);
    queries[i] = make_tuple(a - 1, b - 1, i);
  }
  sort(queries.begin(), queries.end(), compare);
  int l = 0, r = -1;
  int count = 0;
  for (int i = 0; i < m; i++) {
    int a = get<0>(queries[i]), b = get<1>(queries[i]);
    while (l > a) {
      l--;
      arr[sequence[l]] += 1;
      if (arr[sequence[l]] == sequence[l]) {
        count++;
      } else if (arr[sequence[l]] == sequence[l] + 1) {
        count--;
      }
    }
    while (r < b) {
      r++;
      arr[sequence[r]] += 1;
      if (arr[sequence[r]] == sequence[r]) {
        count++;
      } else if (arr[sequence[r]] == sequence[r] + 1) {
        count--;
      }
    }
    while (l < a) {
      arr[sequence[l]] -= 1;
      if (arr[sequence[l]] == sequence[l]) {
        count++;
      } else if (arr[sequence[l]] == sequence[l] - 1) {
        count--;
      }
      l++;
    }
    while (r > b) {
      arr[sequence[r]] -= 1;
      if (arr[sequence[r]] == sequence[r]) {
        count++;
      } else if (arr[sequence[r]] == sequence[r] - 1) {
        count--;
      }
      r--;
    }
    answers[get<2>(queries[i])] = count;
  }
  for (int i = 0; i < m; i++) printf("%d\n", answers[i]);
  return 0;
}
