776A - A Serial Killer.cpp

//http://codeforces.com/problemset/problem/776/A
#include <bits/stdc++.h>
using namespace std;

//Macros
#define PI 3.14159265359
#define all(v) v.begin(),v.end()
#define sortva(v) sort(all(v))
#define sortvd(v) sort(v.rbegin(),v.rend())
#define sortaa(a,n) sort(a,a+n)
#define sortad(a,n) sort(a,a+n),reverse(a,a+n)
#define sfi1(v) scanf("%d",&v)
#define sfi2(v1,v2) scanf("%d %d",&v1,&v2)
#define sfi3(v1,v2,v3) scanf("%d %d %d",&v1,&v2,&v3)
#define sfll1(v) scanf("%I64d",&v);
#define sfll2(v1,v2) scanf("%I64d %I64d",&v1,&v2)
#define sfll3(v1,v2,v3) scanf("%I64d %I64d %I64d",&v1,&v2,&v3)
#define sfstr(v) scanf("%s", v);
#define sz(v) (int)v.size()
#define ndl puts("")
#define SS stringstream
#define F first
#define S second
#define pb push_back
#define mp make_pair
#define loop(i,a,b) for (int i = a; i < (b); i++)
#define prec setprecision(n)
#define endl '\n'

//Short code
typedef long long ll;
typedef vector<int> vi;
typedef vector<long long> vll;
typedef pair<int,int> pi;
typedef unsigned long long ull;
typedef long double ld;


int main ()
{
  #ifndef ONLINE_JUDGE
  	freopen ("input.txt","r",stdin);
  	//freopen ("output.txt","w",stdout);
  #endif
  

    ios::sync_with_stdio(false);
    cin.tie(0);
    cout.tie(0);
    
    int n;
    pair<string, string> p;
    string f, s;
    
    cin>>f >>s;
    cout<< f<< " "<< s<<endl;
    p = mp(f,s);
    cin>>n; cin.ignore();
    while(n--){
    	cin>>f >>s;
    	if(p.F == f)
    		p.F = s;
    	else
    		p.S = s;
    	cout<<p.F << " "<< p.S<<endl;
	}

  //fclose (stdin);
  //fclose (stdout);
  return 0;
}