#pragma GCC optimize "O3,omit-frame-pointer,inline"
#pragma GCC push_options
#pragma GCC optimize ("unroll-loops")
#define _USE_MATH_DEFINES
#include <bits/stdc++.h>
using namespace std;

signed main () {
  std::ios::sync_with_stdio(false); std::cin.tie(0);
  int n;
  cin >> n;

  string ans;
  for (int u = 0; u < n; u++) {
    vector<int> cnt(25);
    for (int i = 0; i < 25; i++) {
      char ch = 'a' + i;
      string t;
      for (int v = 0; v < n; v++) {
        if (v == u) {
          t += ch;
        } else {
          t += 'z';
        }
      }
      cout << "? " << t << endl;
      cin >> cnt[i];
    }
    // cntの最大値を求める
    int max_cnt = *max_element(cnt.begin(), cnt.end());
    // cntの最大値の個数を求める
    int max_cnt_cnt = count(cnt.begin(), cnt.end(), max_cnt);
    if (max_cnt_cnt > 1) {
      ans += 'z';
    } else {
      ans += 'a' + distance(cnt.begin(), max_element(cnt.begin(), cnt.end()));
    }
  }

  cout << "! " << ans << endl;
  return 0;  
}