#include #define rep(i,n) for(int i = 0; i < (n); ++i) #define srep(i,s,t) for (int i = s; i < t; ++i) #define drep(i,n) for(int i = (n)-1; i >= 0; --i) using namespace std; typedef long long int ll; typedef pair P; #define yn {puts("YES");}else{puts("NO");} #define MAX_N 200005 int main() { int n; cin >> n; string s[n * 2]; rep(i,n)cin >> s[i]; sort(s,s+n); rep(i,n)s[i+n] = s[i]; int flag = 1; rep(i,n){ if(n % 2 == 0){ if(s[i] == s[i+n/2])flag = 0; }else{ if(s[i] == s[i+n/2+1])flag = 0; } } if(flag)yn; return 0; }