#pragma GCC optimize("O3")
#include<bits/stdc++.h>
using namespace std;
struct node
{
int s, e, m;
vector<int> v;
node *l = nullptr, *r = nullptr;
node(int s, int e) {
this->s = s; this->e = e; this->m = (s+e)/2;
if (s == e) return;
l = new node(s, m);
r = new node(m+1, e);
}
void build(vector<int>& A) {
if (s == e) {
v = {A[s]};
return;
}
// build children
l->build(A);
r->build(A);
v.resize(l->v.size()+r->v.size());
// merge l, r
ranges::merge(l->v, r->v, v.begin());
}
int query(int x, int y, int val) {
// number of elements >= val in x..y
// if not covered
if (e < x || y < s) return 0;
// if completely covered
if (x <= s && e <= y) {
auto it = lower_bound(v.begin(), v.end(), val);
auto num = v.size() - (it - v.begin());
return num;
}
// partially covered
return (l->query(x,y,val) + r->query(x,y,val));
}
};
int n, q;
int query(node *seg, int l, int r) {
int low = 0, high = n+5;
int ans = 0;
while (low < high) {
int mid = (low+high)/2; // number of citations
int res = seg->query(l,r,mid);
if (res >= mid) {
// too many can fit the description, try increasing mid
ans = mid;
low = mid+1;
}
else {
high = mid;
}
}
return ans;
}
int main() {
ios::sync_with_stdio(false); cin.tie(nullptr);
cin >> n >> q;
vector<int> A(n); for (int i = 0; i < n; i++) cin >> A[i];
node *seg = new node(0, n-1);
seg->build(A);
while (q--) {
int l,r; cin >> l >> r; l--,r--;
cout << query(seg, l, r) << "\n";
}
}
