#define _CRT_SECURE_NO_WARNINGS
#define _USE_MATH_DEFINES
#include <stdio.h>
#include <algorithm>
#include <utility>
#include <functional>
#include <cstring>
#include <queue>
#include <stack>
#include <math.h>
#include <iterator>
#include <iomanip>
#include <vector>
#include <string>
#include <set>
#include <math.h>
#include <iostream> 
#include<map>
#include <list>
#include <typeinfo>
using namespace std;
#define REP(a,b) for(long long a = 0;a < b;++a)
int hoge[1000000] = {};
int main() {
	//文字列をint化してからぶち込んでソート
	int n;
	scanf("%d", &n);
	REP(i, n) {
		string hogee;
		cin >> hogee;
		hoge[1000 * (int)hogee[0] + (int)hogee[1]]++;
	}
	sort(hoge, hoge + 900000, greater<int>());
	int ans = n / 2;
	if (n % 2 == 1) ans++;
	if (ans >= hoge[0]) {
		cout << "YES" << endl;
	}
	else {
		cout << "NO" << endl;
	}
}
//thank you for reading my code!