#include <bits/stdc++.h>
using namespace std;
int l[1000006],r[1000006],ans[1000006];
struct node{
	int l,r,id;
	friend bool operator<(node a,node b){
		return a.l<b.l;
	}
}a[1000006];
struct segnode{
	int val,tag;
	void plz(int u){
		val+=u;
		tag+=u;
	}
}seg[4000006];
void push_down(int u){
	seg[u<<1].plz(seg[u].tag);
	seg[u<<1|1].plz(seg[u].tag);
	seg[u].tag=0;
}
int query(int u,int l,int r,int val){
	if(seg[u].val<=val)return l-1;
	if(l==r)return l;
	push_down(u);
	int mid=l+r>>1;
	if(seg[u<<1|1].val>val){
		return query(u<<1|1,mid+1,r,val);
	}else return query(u<<1,l,mid,val);
}
void update(int u,int l,int r,int ql,int qr){
	if(ql>qr)return ;
	if(ql<=l&&r<=qr){
		seg[u].plz(1);
		return ;
	}push_down(u);
	int mid=l+r>>1;
	if(ql<=mid)update(u<<1,l,mid,ql,qr);
	if(qr>mid)update(u<<1|1,mid+1,r,ql,qr);
	seg[u].val=max(seg[u<<1].val,seg[u<<1|1].val);
}
vector<pair<int,int> >g[1000006];
int push(int u,int l,int r,int pos){
	if(l==r){
		return seg[u].val;
	}
	int mid=l+r>>1;
	push_down(u);
	if(pos<=mid)return push(u<<1,l,mid,pos);
	else return push(u<<1|1,mid+1,r,pos);
}
int id[1000006];
int main(){
	int n,q;
	cin>>n>>q;
	for(int i=1;i<=n;i++){
		cin>>l[i]>>r[i];
	}
	for(int i=1;i<=q;i++){
		cin>>a[i].l>>a[i].r;
		a[i].id=i;
		g[a[i].r].push_back({a[i].l,a[i].id});
	}
	sort(a+1,a+1+q);
	for(int i=1;i<=q;i++){
		id[a[i].l]=i;
	}
	int pos=1;
	for(int i=1;i<=n;i++){
		while(a[pos].l==i)pos++;
		update(1,1,n,max(1,query(1,1,n,r[i])+1),min(query(1,1,n,l[i]-1),i));
		for(pair<int,int>a:g[i]){
			ans[a.second]=push(1,1,n,a.first);
		}
//		COUT<<PUSH(1,1,N)
	}
	for(int i=1;i<=q;i++){
		cout<<ans[i]<<'\n';
	}
}
/*
things to check
0.delete cerr code or use '//'
1.initallize(especially multicases)
2.int overflow/long long mle
3.if make the ans is hard , try 2-divided
4.memory &b-&a
5.function canshu position
6.the format of input
7.size enough ?
8.the name of function
9.stop copying x0->y0
*/