#include <bits/stdc++.h>
#define ll long long
#define ull unsigned ll
#define pb push_back
#define pa pair<int, int>
#define pall pair<ll, int>
#define fi first
#define se second
#define TASK "test"
#define Size(x) (int) x.size()
#define all(x) x.begin(), x.end()
using namespace std;
template<typename T1, typename T2> bool mini (T1 &a, T2 b) {if(a > b) a = b; else return 0; return 1;}
template<typename T1, typename T2> bool maxi (T1 &a, T2 b) {if(a < b) a = b; else return 0; return 1;}
const int MOD = 1e9 + 7;
const int LOG = 20;
const int maxn = 2e5 + 7;
const ll oo = 1e18 + 69;
int n, q, a[maxn], u, v;
struct ST {
struct node {
vector<int> x;
friend node operator + (node &a, node &b) {
node c;
int i = 0, j = 0;
while(i < Size(a.x) || j < Size(b.x)) {
if(j == Size(b.x) || (i != Size(a.x) && a.x[i] < b.x[j])) c.x.pb(a.x[i++]);
else c.x.pb(b.x[j++]);
}
return c;
}
};
node st[4 * maxn];
void build(int id, int l, int r) {
if(l == r) {
st[id].x.pb(a[l]);
return;
}
int mid = l + r >> 1;
build(id << 1, l, mid);
build(id << 1 | 1, mid + 1, r);
st[id] = st[id << 1] + st[id << 1 | 1];
}
int get(int id, int l, int r, int u, int v, int x) {
if(r < u || l > v) return 0;
if(u <= l && r <= v) {
int idd = lower_bound(all(st[id].x), x) - st[id].x.begin();
return Size(st[id].x) - idd;
}
int mid = l + r >> 1;
return get(id << 1, l, mid, u, v, x) + get(id << 1 | 1, mid + 1, r, u, v, x);
}
} st;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(NULL);
//freopen(TASK".inp", "r", stdin);
//freopen(TASK".out", "w", stdout);
cin>>n>>q;
for(int i = 1; i <= n; i++) cin>>a[i];
st.build(1, 1, n);
while(q--) {
cin>>u>>v;
int l = 1, r = (v - u + 1), res = 0, mid;
while(l <= r) {
mid = l + r >> 1;
if(st.get(1, 1, n, u, v, mid) >= mid) {
res = mid;
l = mid + 1;
} else r = mid - 1;
}
cout<<res<<"\n";
}
return 0;
}
