//#include <monsterenergy>
#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
const int MAX = 1e9;
const int MIN = -1*1e9;
const ll MAXLL = 1e18;
const ll MINLL = -1*1e18;

int main()
{
    char C; cin >> C;
    set<pair<char,char>> Ans;
    vector<pair<int,char>> Count(200);
    for(int i = 0; i < 200; i++) Count[i] = {MAX,'?'};
    for(char i = 'a'; i <= 'z'; i++) Count[i] = {26,i};
    cout << "?" << " " << C << C << endl;
    Ans.insert({C,C});
    Count[C].first--;

    while(true)
    {
        string S,S2; cin >> S2 >> S; 
        if(S2 == "!") return 0;
        Ans.insert({S[0],S[1]});

        Count[S[0]].first--;
        sort(all(Count));
        bool f = false;
        for(int i = 0; i < 100; i++)
        {
            char A = S[1];
            char B = Count[i].second;
            if(Ans.count({A,B}))
            {
                cout << "?" << " " << A << B << endl;
            }
            else continue;
            f = true;
            Count[A].first--;
            Ans.insert({A,B});
            break;
        }
    }
    return 0;
}