#include <bits/stdc++.h>   using namespace std;   const int MAXN = 105;   string name[MAXN], surname[MAXN];   bool u[MAXN];   int n;   int x1[30], x2[30];   int Getn() {     int res = 0;     for (int i = 0; i < 26; i++) res += min(x1[i], x2[i]);     return res;   }   int main() {     cin >> n;     for (int i = 1; i <= n; i++) cin >> name[i];     for (int i = 1; i <= n; i++) cin >> surname[i];     sort(name + 1, name + n + 1);     sort(surname + 1, surname + n + 1);     for (int i = 1; i <= n; i++) x1[name[i][0] -  A ]++;     for (int i = 1; i <= n; i++) x2[surname[i][0] -  A ]++;     for (int i = 1; i <= n; i++) {       for (int j = 1; j <= n; j++)         if (!u[j]) {           int c = Getn();           x1[name[i][0] -  A ]--;           x2[surname[j][0] -  A ]--;           if (Getn() != c - (name[i][0] == surname[j][0])) {             x1[name[i][0] -  A ]++;             x2[surname[j][0] -  A ]++;             continue;           }           u[j] = true;           cout << name[i] <<     << surname[j];           if (i != n)             cout <<  ,  ;           else             cout << endl;           break;         }     }     return 0;   }   