#include <bits/stdc++.h>
using namespace std;
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
//#include "light.h"
#define int long long
 
typedef pair<int,int> pii;
typedef vector<int> vi;
typedef vector<pii> vii;
typedef vector<bool> vb;
typedef long long ll;
typedef pair<ll,ll> pll;
typedef vector<pll> vll;
 
typedef tree<pii,null_type,less<pii>,rb_tree_tag,
tree_order_statistics_node_update> oset;
 
#define fi first
#define se second
#define pb push_back
#define pf push_front
 
#define mid (l+r)/2
#define all(x) x.begin(),x.end()
#define FOR(i,a) for(int i=0;i<(a);i++)
#define FORE(i,a,b) for(int i=(a);i<(b);i++)
 
#define cont(x) for(auto el:x) cout<<el<<' ';cout<<endl;
#define contp(x) for(auto el:x) cout<<el.fi<<'-'<<el.se<<' ';cout<<endl;
#define sp <<" "<<
 
#define DEBUG(x) cout<<(#x) sp x<<endl
#define carp(a,b) (((a%MOD)*(b%MOD))%MOD)
#define topla(a,b) (((a%MOD)+(b%MOD))%MOD)
 
const ll INF=1e18;
const int MAXN=1e5+5;
const int MOD=1e9+7;
int n,s,t;
int ans;
vii a;
signed main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    
    cin>>n>>s>>t;
    a.resize(n);
    FOR(i,n){
        cin>>a[i].fi>>a[i].se;
    }
    ans=-1;
    for(int mask=0;mask<(1<<n);mask++){
        vi bir(t+1,0);
        vi iki(t+1,0);
        for(int bt=0;bt<n;bt++){
            if(mask&(1<<bt)){
                iki[a[bt].fi]++;
                bir[a[bt].se]++;
            }
            else{
                bir[a[bt].fi]++;
                iki[a[bt].se]++;
            }
        }
        bool f=true;
        FOR(i,n){
            if(abs(bir[a[i].fi]-iki[a[i].fi])>1){
                f=false;
                break;
            }
            if(abs(bir[a[i].se]-iki[a[i].se])>1){
                f=false;
                break;
            }
        }
        
        if(f){
            ans=mask;
            break;
        }
    }
    for(int bt=0;bt<n;bt++){
        if(ans&(1<<bt)) swap(a[bt].fi,a[bt].se);
    }
    for(auto el:a) cout<<el.fi sp el.se<<endl;
}
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