#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
#define ll long long
template<typename T>
using ordered_multiset = tree<T, null_type, less_equal<T>, rb_tree_tag, tree_order_statistics_node_update>;

typedef long double ld;


#define lmao ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);

mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

const int N = 1e6+5 , M = 1e4+5 , MOD = 1e9+7, LOG = 20 , Msk = 21 , pw1 = 31 , pwe2 = 37;

struct Point{
    ld x = -1 , y = -1;
    bool Fixed = true;
};

void testCase() {
    int n , m;
    cin >> n >> m;
    vector<Point>v(n);
    for(int i = 0 ; i < n ; i++){
        cin >> v[i].x >> v[i].y;
        if(v[i].x == -1 && v[i].y == -1)
            v[i].Fixed = false;
    }
    vector<vector<int>>adj(n + 1);
    for(int i = 0 , u , w ; i < m ; i++)
        cin >> u >> w , adj[u - 1].push_back(w - 1) , adj[w - 1].push_back(u - 1);

    for(int i = 0 ; i < 1e5 ; i++){
        for(int j = 0 ; j < n ; j++){
            if(v[j].Fixed)
                continue;
            ld sumX = 0 , sumY = 0;
            for(auto child : adj[j]){
                sumX += v[child].x;
                sumY += v[child].y;
            }
            v[j].x = (sumX / adj[j].size());
            v[j].y = (sumY / adj[j].size());
        }
    }
    for(auto [x , y , _] : v)
        cout << x <<" "  << y <<'\n';
}

signed main() {

    lmao
    int t = 1;
//    cin >> t;

    while (t--)
        testCase();
}