#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 10;
int n, m, l = 1, r, tot, block, a[maxn], sum[maxn], ans[maxn];
struct query {
  int l, r, id;
} q[maxn];
bool cmp(query a, query b) {
  if (a.l / block == b.l / block) return a.r < b.r;
  return a.l < b.l;
}
void add(int x) {
  if (a[x] > n) return;
  if (sum[a[x]] == a[x]) tot--;
  sum[a[x]]++;
  if (sum[a[x]] == a[x]) tot++;
}
void del(int x) {
  if (a[x] > n) return;
  if (sum[a[x]] == a[x]) tot--;
  sum[a[x]]--;
  if (sum[a[x]] == a[x]) tot++;
}
int main() {
  scanf("%d%d", &n, &m);
  for (int i = 1; i <= n; i++) scanf("%d", &a[i]);
  block = sqrt(n);
  for (int i = 1; i <= m; i++) scanf("%d%d", &q[i].l, &q[i].r), q[i].id = i;
  sort(q + 1, q + m + 1, cmp);
  for (int i = 1; i <= m; i++) {
    while (l > q[i].l) add(--l);
    while (r < q[i].r) add(++r);
    while (l < q[i].l) del(l++);
    while (r > q[i].r) del(r--);
    ans[q[i].id] = tot;
  }
  for (int i = 1; i <= m; i++) printf("%d\n", ans[i]);
  return 0;
}
