2D Traveling

#include<bits/stdc++.h>
using namespace std;
#include<cstring>
#include<cstdio>
#include<vector>
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
template<class T> using indexed_set = tree<T, null_type, less<T>, 
            rb_tree_tag, tree_order_statistics_node_update>;


#define rep(i,a,b) for(int i=a;i<b;i++)
#define int long long
#define pf push_front
#define pb push_back
#define ppf pop_front()
#define ppb pop_back()
#define in insert
#define mp make_pair
#define f first
#define sd second
#define all(x) x.begin(), x.end()
#define mx(x) *max_element(all(x))
#define mn(x) *min_element(all(x))
#define cy cout<<"YES"<<'\n';
#define cn cout<<"NO"<<'\n';

#define PI 3.1415926535897932384626 

typedef pair<int, int>	pii;
typedef vector<int>	vi;
typedef vector<string>	vs;
typedef vector<pii>	vpii;
typedef vector<vi>	vvi;


//segment tree setup for maximum range
// void build(int ind,int low,int high,vector<int> &a,vi &seg){
//     if(low==high){
//         seg[ind]=a[low];
//         return;
//     }
    
//     int mid=(low+high)/2;
//     build(2*ind+1,low,mid,a,seg);
//     build(2*ind+2,mid+1,high,a,seg);
//     seg[ind]=max(seg[2*ind+1],seg[2*ind+2]);
// }

// ///

// int query(int ind,int low,int high,int l,int r,vi &seg){
    
//     if(low>=l && high<=r){
//         return seg[ind];
//     }
    
//     if(high<l || low>r) return INT_MIN;
    
//     int mid=(low+high)/2;
//     int left=query(2*ind+1,low,mid,l,r,seg);
//     int right=query(2*ind+2,mid+1,high,l,r,seg);
    
//     return max(left,right);
// }

///


// 48-57 -> 0-9
// 65-90 -> A-Z
// 97-122 -> a-z

// void setIO(string s) {
// 	freopen((s + ".in").c_str(), "r", stdin);
// 	freopen((s + ".out").c_str(), "w", stdout);
// }


void solve()
{
    int n,k,a,b;
    cin>>n>>k>>a>>b;
    
    vpii arr(n+1);
    rep(i,1,n+1)
    {
        int x,y;
        cin>>x>>y;
        arr[i]={x,y};
    }
    int dis1=1e12,dis2=1e12;
    
    rep(i,1,k+1)
    {
        dis1=min(dis1,abs(arr[i].f-arr[a].f)+abs(arr[i].sd-arr[a].sd));
        dis2=min(dis2,abs(arr[i].f-arr[b].f)+abs(arr[i].sd-arr[b].sd));
    }
   
    int dis3=abs(arr[a].f-arr[b].f)+abs(arr[a].sd-arr[b].sd);
    cout<<min(dis1+dis2,dis3)<<'\n';
}

signed main(){

//setIO("problemname");

    ios::sync_with_stdio(false);
	cin.tie(nullptr);
        int t;
        cin>>t;
        while(t--){
        solve();
       }
	
}