#include <bits/stdc++.h>
using namespace std;
const int maxn = 111111;
int sum[500][maxn], a[maxn], b[maxn], c[500];
int main() {
  int n, m;
  while (scanf("%d%d", &n, &m) != EOF) {
    for (int i = 0; i < n; i++) {
      scanf("%d", &a[i]);
      if (a[i] <= n) b[a[i]]++;
    }
    int t = 0, num = 0;
    for (int i = 1; i <= n; i++) {
      if (b[i] >= i) c[t++] = i;
    }
    for (int i = 0; i < t; i++) {
      for (int j = 1; j <= n; j++)
        if (c[i] == a[j - 1])
          sum[i][j] = sum[i][j - 1] + 1;
        else
          sum[i][j] = sum[i][j - 1];
    }
    while (m--) {
      int l, r;
      scanf("%d%d", &l, &r);
      num = 0;
      for (int i = 0; i < t; i++)
        if (sum[i][r] - sum[i][l - 1] == c[i]) num++;
      printf("%d\n", num);
    }
  }
  return 0;
}
