#include <bits/stdc++.h>
using namespace std;
#pragma comment(linker, “/ STACK : 268435456”)
template <class T>
inline int size(const T& c) {
  return c.size();
}
template <class T>
inline int lenght(const T& c) {
  return c.length();
}
int n, m;
int a[100011];
vector<int> b;
int f[100011][450];
int cnt[100011];
int main() {
  scanf("%d", &n);
  scanf("%d", &m);
  memset(cnt, 0, sizeof cnt);
  for (int i = (1), _b = (n); i <= _b; i++) {
    scanf("%d", &a[i]);
    if (a[i] <= n) cnt[a[i]]++;
  }
  b.clear();
  for (int i = (1), _b = (n); i <= _b; i++)
    if (cnt[i] >= i) (b).push_back((i));
  memset(f[0], 0, sizeof f[0]);
  for (int i = (1), _b = (n); i <= _b; i++)
    for (int j = (0), _b = ((b.size()) - 1); j <= _b; j++)
      f[i][j] = f[i - 1][j] + (a[i] == b[j]);
  for (int i = (0), _b = ((m)-1); i <= _b; i++) {
    int u, v;
    scanf("%d", &u);
    scanf("%d", &v);
    int ret = 0;
    for (int j = (0), _b = ((b.size()) - 1); j <= _b; j++)
      ret += (f[v][j] - f[u - 1][j]) == b[j];
    printf("%d ", ret);
    printf("\n");
  }
  return 0;
}
