#include <bits/stdc++.h>
using namespace std;
bool __insideGrid(int x, int y, int h, int w, int sx = 0, int sy = 0) {
  if (x < sx) return false;
  if (y < sy) return false;
  if (x >= sx + h) return false;
  if (y >= sy + w) return false;
  return true;
}
const double pi = acos(-1.0);
int data[100005];
int freq[100005];
bool visited[100005] = {0};
int occur[500][100005];
int num[500];
int main() {
  int n, m;
  scanf("%d", &(n));
  scanf("%d", &(m));
  for (int i = 1; i <= n; i++) {
    scanf("%d", &(data[i]));
    if (data[i] <= n) freq[data[i]]++;
  }
  int occurSZ = 0;
  for (int i = 1; i <= n; i++) {
    if (data[i] > n) continue;
    if (visited[data[i]]) continue;
    if (freq[data[i]] >= data[i]) {
      visited[data[i]] = 1;
      num[occurSZ] = data[i];
      occur[occurSZ][0] = 0;
      for (int j = 1; j <= n; j++) {
        if (data[j] == data[i])
          occur[occurSZ][j] = occur[occurSZ][j - 1] + 1;
        else
          occur[occurSZ][j] = occur[occurSZ][j - 1];
      }
      occurSZ++;
    }
  }
  int L, R;
  for (int i = 0; i < m; i++) {
    scanf("%d", &(L));
    scanf("%d", &(R));
    int ans = 0;
    for (int j = 0; j < occurSZ; j++) {
      int temp = occur[j][R] - occur[j][L - 1];
      if (temp == num[j]) ans++;
    }
    printf("%d\n", ans);
  }
  return 0;
}
