#include<bits/stdc++.h>
#define Gc() getchar() 
#define Me(x,y) memset(x,y,sizeof(x))
#define Mc(x,y) memcpy(x,y,sizeof(x))
#define d(x,y) ((m)*(x-1)+(y))
#define R(n) (rnd()%(n)+1)
#define Pc(x) putchar(x)
#define LB lower_bound
#define UB upper_bound
#define PB push_back
using ll=long long;using db=double;using lb=long db;using ui=unsigned;using ull=unsigned ll;
using namespace std;const int N=1e6+5,M=N*22+5,K=2e3+5,mod=924844033,Mod=mod-1;const db eps=1e-9;const ll INF=1e18+7;mt19937 rnd(time(0));
int n,m,k,x,y,z;string A;
int Qry(string A){
	cout<<A<<endl;
	string S;cin>>S>>S;
	if(S=="GRANTED")exit(0);
	char c=Gc();c=Gc();c=Gc();
	int x=0;while(c>='0'&&c<='9') x=x*10+c-48,c=Gc();
	c=Gc();c=Gc();c=Gc();return x; 
}
int main(){
	int i,j;for(i=1;i<=20;i++){
		A+='a';
		if(Qry(A)^5) {n=i;break;}
	} 
	for(i=1;i<=n;i++){
		char Id=0;
		for(j=0;j<26;j++){
			A[i-1]='a'+j;
			int p=Qry(A);
			if(p>i*9+5){Id=A[i-1];break;} 
		} 
		for(j=0;j<26;j++){
			A[i-1]='A'+j;
			int p=Qry(A);
			if(p>i*9+5) {Id=A[i-1];break;}
		}
		for(j=0;j<10;j++){
			A[i-1]='0'+j;
			int p=Qry(A);
			if(p>i*9+5){Id=A[i-1];break;}
		}
		A[i-1]=Id;
	}
}