#include<bits/stdc++.h>
using namespace std;
static bool cmp(vector<int>& a,vector<int>& b)
{
    if(a[0]<b[0])
        return true;
    else
        return false;
}
 void asb(long long node,int i,int j,vector<vector<int>>&  nums,vector<int>& a)
    {

        if(i==j)
        {
            a[node]=nums[i][1];
            return ;
        }
        else
        {
            int mid=i+(j-i)/2;
            asb(2*node+1,i,mid,nums,a);
            asb(2*node+2,mid+1,j,nums,a);
            a[node]=max(a[2*node+1],a[2*node+2]);
        }
    }
 int maxval(int start,int end,int l,int r,long long node,vector<int>& a)
    {
        if(start==l && end==r)
        {
            return a[node];
        }
        else
        {

            int mid=start+(end-start)/2;
            if(l<=mid && r>mid)
            {
                int f=maxval(start,mid,l,mid,2*node+1,a);
                int b=maxval(mid+1,end,mid+1,r,2*node+2,a);
                return max(f,b);
            }
            if(r<=mid)
                return maxval(start,mid,l,r,2*node+1,a);
            else
                return maxval(mid+1,end,l,r,2*node+2,a);

        }
    }
int maxRange(vector<int>& a,int left, int right,int size) {


       int d=maxval(0,size,left,right,0,a);


        return d;
    }





vector<int> solve(int N ,vector<vector<int>>& arr,int Q,vector<vector<int>> & query)
{
    vector<int> a(4*arr.size());
    sort(arr.begin(),arr.end(),cmp);
    asb(0,0,arr.size()-1,arr,a);
    vector<int> ans;

   for(auto i: query)
   { sort(i.begin(),i.end());
       int start=0,end=arr.size()-1;
       while(start<=end)
       {
           int mid=start+(end-start)/2;
           if(arr[mid][0]>=i[0])
               end=mid-1;
           else
               start=mid+1;

       }
    int start_idx=start;
    start=0,end=arr.size()-1;
       while(start<=end)
       {
           int mid=start+(end-start)/2;
           if(arr[mid][0]>i[1])
               end=mid-1;
           else
               start=mid+1;
       }
      if(start_idx>end)
          ans.push_back(-1);
    else
        ans.push_back(maxRange(a,start_idx,end,arr.size()-1));

   }

    return ans;
}